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Equations/183278: how do you solve 3w-4=w+8
1 solutions

Answer 137613 by jim_thompson5910(28476) About Me  on 2009-02-22 21:29:25 (Show Source):
You can put this solution on YOUR website!

3w-4=w%2B8 Start with the given equation.


3w=w%2B8%2B4 Add 4 to both sides.


3w-w=8%2B4 Subtract w from both sides.


2w=8%2B4 Combine like terms on the left side.


2w=12 Combine like terms on the right side.


w=%2812%29%2F%282%29 Divide both sides by 2 to isolate w.


w=6 Reduce.


----------------------------------------------------------------------

Answer:

So the answer is w=6


Equations/183231: This question is from textbook integrated algebra 1
15x-3(3x+4)=6
1 solutions

Answer 137611 by jim_thompson5910(28476) About Me  on 2009-02-22 21:17:09 (Show Source):
You can put this solution on YOUR website!

15x-3%283x%2B4%29=6 Start with the given equation.


15x-9x-12=6 Distribute.


6x-12=6 Combine like terms on the left side.


6x=6%2B12 Add 12 to both sides.


6x=18 Combine like terms on the right side.


x=%2818%29%2F%286%29 Divide both sides by 6 to isolate x.


x=3 Reduce.


----------------------------------------------------------------------

Answer:

So the answer is x=3


Expressions-with-variables/183267: How do you factor (x^2+2xy+y^2)-4w^2?
1 solutions

Answer 137610 by jim_thompson5910(28476) About Me  on 2009-02-22 21:12:01 (Show Source):
You can put this solution on YOUR website!
%28x%5E2%2B2xy%2By%5E2%29-4w%5E2 Start with the given expression.


First, we need to factor x%5E2%2B2xy%2By%5E2




Looking at x%5E2%2B2xy%2By%5E2 we can see that the first term is x%5E2 and the last term is y%5E2 where the coefficients are 1 and 1 respectively.

Now multiply the first coefficient 1 and the last coefficient 1 to get 1. Now what two numbers multiply to 1 and add to the middle coefficient 2? Let's list all of the factors of 1:



Factors of 1:
1

-1 ...List the negative factors as well. This will allow us to find all possible combinations

These factors pair up and multiply to 1
1*1
(-1)*(-1)

note: remember two negative numbers multiplied together make a positive number


Now which of these pairs add to 2? Lets make a table of all of the pairs of factors we multiplied and see which two numbers add to 2

First NumberSecond NumberSum
111+1=2
-1-1-1+(-1)=-2



From this list we can see that 1 and 1 add up to 2 and multiply to 1


Now looking at the expression x%5E2%2B2xy%2By%5E2, replace 2xy with xy%2Bxy (notice xy%2Bxy adds up to 2xy. So it is equivalent to 2xy)

x%5E2%2Bhighlight%28xy%2Bxy%29%2By%5E2


Now let's factor x%5E2%2Bxy%2Bxy%2By%5E2 by grouping:


%28x%5E2%2Bxy%29%2B%28xy%2By%5E2%29 Group like terms


x%28x%2By%29%2By%28x%2By%29 Factor out the GCF of x out of the first group. Factor out the GCF of y out of the second group


%28x%2By%29%28x%2By%29 Since we have a common term of x%2By, we can combine like terms


So x%5E2%2Bxy%2Bxy%2By%5E2 factors to %28x%2By%29%28x%2By%29


So this also means that x%5E2%2B2xy%2By%5E2 factors to %28x%2By%29%28x%2By%29 (since x%5E2%2B2xy%2B1y%5E2 is equivalent to x%5E2%2Bxy%2Bxy%2By%5E2)


note: %28x%2By%29%28x%2By%29 is equivalent to %28x%2By%29%5E2 since the term x%2By occurs twice. So x%5E2%2B2xy%2By%5E2 also factors to %28x%2By%29%5E2


So x%5E2%2B2xy%2By%5E2 factors to %28x%2By%29%5E2


---------------------------------------------------------------


So the original expression %28x%5E2%2B2xy%2By%5E2%29-4w%5E2 becomes %28x%2By%29%5E2-4w%5E2


%28x%2By%29%5E2-%282w%29%5E2 Rewrite 4w%5E2 as %282w%29%5E2


Notice how we now have a difference of squares. Remember, the difference of squares formula is A%5E2-B%5E2=%28A%2BB%29%28A-B%29


In this case, A=x%2By and B=2w


Now plug them in the formula to get:


%28x%2By%29%5E2-%282w%29%5E2=%28x%2By%2B2w%29%28x%2By-2w%29



==================================================

Answer:


So this means that %28x%2By%29%5E2-%282w%29%5E2 factors to %28x%2By%2B2w%29%28x%2By-2w%29


Equivalently, this means that %28x%5E2%2B2xy%2By%5E2%29-4w%5E2 factors to %28x%2By%2B2w%29%28x%2By-2w%29


Linear-systems/183269: Use elimination method:tnx
5x-3y=32
4x+3y=4

1 solutions

Answer 137609 by jim_thompson5910(28476) About Me  on 2009-02-22 21:04:56 (Show Source):
You can put this solution on YOUR website!

Start with the given system of equations:
system%285x-3y=32%2C4x%2B3y=4%29


Add the equations together. You can do this by simply adding the two left sides and the two right sides separately like this:


%285x-3y%29%2B%284x%2B3y%29=%2832%29%2B%284%29


%285x%2B4x%29%2B%28-3y%2B3y%29=32%2B4 Group like terms.


9x%2B0y=36 Combine like terms.


9x=36 Simplify.


x=%2836%29%2F%289%29 Divide both sides by 9 to isolate x.


x=4 Reduce.


------------------------------------------------------------------


5x-3y=32 Now go back to the first equation.


5%284%29-3y=32 Plug in x=4.


20-3y=32 Multiply.


-3y=32-20 Subtract 20 from both sides.


-3y=12 Combine like terms on the right side.


y=%2812%29%2F%28-3%29 Divide both sides by -3 to isolate y.


y=-4 Reduce.


So the solutions are x=4 and y=-4.


Which form the ordered pair .


This means that the system is consistent and independent.


Notice when we graph the equations, we see that they intersect at . So this visually verifies our answer.


Graph of 5x-3y=32 (red) and 4x%2B3y=4 (green)


Linear-systems/183271: Use elimination method
4x-y=8
2x+y=4
1 solutions

Answer 137605 by jim_thompson5910(28476) About Me  on 2009-02-22 20:53:57 (Show Source):
You can put this solution on YOUR website!

Start with the given system of equations:
system%284x-y=8%2C2x%2By=4%29


Add the equations together. You can do this by simply adding the two left sides and the two right sides separately like this:


%284x-1y%29%2B%282x%2By%29=%288%29%2B%284%29


%284x%2B2x%29%2B%28-1y%2B1y%29=8%2B4 Group like terms.


6x%2B0y=12 Combine like terms.


6x=12 Simplify.


x=%2812%29%2F%286%29 Divide both sides by 6 to isolate x.


x=2 Reduce.


------------------------------------------------------------------


4x-1y=8 Now go back to the first equation.


4%282%29-1y=8 Plug in x=2.


8-1y=8 Multiply.


-y=8-8 Subtract 8 from both sides.


-y=0 Combine like terms on the right side.


y=%280%29%2F%28-1%29 Divide both sides by -1 to isolate y.


y=0 Reduce.


So the solutions are x=2 and y=0.


Which form the ordered pair .


This means that the system is consistent and independent.


Notice when we graph the equations, we see that they intersect at . So this visually verifies our answer.


Graph of 4x-y=8 (red) and 2x%2By=4 (green)


Linear-systems/183268: Use elimination method in solving this:tnx
4x-y=8
2x+y=4
1 solutions

Answer 137604 by jim_thompson5910(28476) About Me  on 2009-02-22 20:53:15 (Show Source):
You can put this solution on YOUR website!

Start with the given system of equations:
system%284x-y=8%2C2x%2By=4%29


Add the equations together. You can do this by simply adding the two left sides and the two right sides separately like this:


%284x-y%29%2B%282x%2By%29=%288%29%2B%284%29


%284x%2B2x%29%2B%28-y%2By%29=8%2B4 Group like terms.


6x%2B0y=12 Combine like terms.


6x=12 Simplify.


x=%2812%29%2F%286%29 Divide both sides by 6 to isolate x.


x=2 Reduce.


------------------------------------------------------------------


4x-y=8 Now go back to the first equation.


4%282%29-y=8 Plug in x=2.


8-y=8 Multiply.


-y=8-8 Subtract 8 from both sides.


-y=0 Combine like terms on the right side.


y=%280%29%2F%28-1%29 Divide both sides by -1 to isolate y.


y=0 Reduce.


So the solutions are x=2 and y=0.


Which form the ordered pair .


This means that the system is consistent and independent.


Notice when we graph the equations, we see that they intersect at . So this visually verifies our answer.


Graph of 4x-y=8 (red) and 2x%2By=4 (green)


Linear-systems/183262: Use elimination method in solving this;tnx
x+3y=5
2x+y=5
1 solutions

Answer 137602 by jim_thompson5910(28476) About Me  on 2009-02-22 20:22:00 (Show Source):
You can put this solution on YOUR website!

Start with the given system of equations:
system%28x%2B3y=5%2C2x%2By=5%29


-2%28x%2B3y%29=-2%285%29 Multiply the both sides of the first equation by -2.


-2x-6y=-10 Distribute and multiply.


So we have the new system of equations:
system%28-2x-6y=-10%2C2x%2By=5%29


Now add the equations together. You can do this by simply adding the two left sides and the two right sides separately like this:


%28-2x-6y%29%2B%282x%2By%29=%28-10%29%2B%285%29


%28-2x%2B2x%29%2B%28-6y%2B1y%29=-10%2B5 Group like terms.


0x%2B-5y=-5 Combine like terms.


-5y=-5 Simplify.


y=%28-5%29%2F%28-5%29 Divide both sides by -5 to isolate y.


y=1 Reduce.


------------------------------------------------------------------


-2x-6y=-10 Now go back to the first equation.


-2x-6%281%29=-10 Plug in y=1.


-2x-6=-10 Multiply.


-2x=-10%2B6 Add 6 to both sides.


-2x=-4 Combine like terms on the right side.


x=%28-4%29%2F%28-2%29 Divide both sides by -2 to isolate x.


x=2 Reduce.


So the solutions are x=2 and y=1.


Which form the ordered pair .


This means that the system is consistent and independent.


Notice when we graph the equations, we see that they intersect at . So this visually verifies our answer.


Graph of x%2B3y=5 (red) and 2x%2By=5 (green)


Angles/183256: This question is from textbook Blitzer- Introductory Algebra
The measure of the angle's supplement is 40 degrees more than 3 times that of its complement. Find the measure of the angle described.
I know the answer is 65 but not sure how to find the answer. This is what I came up with but it doesn't work out correctly.
x=3(180-x)+40
I'd sure appreciate your help. I'm in my 40's and going to college for the first time. Math isn't coming easy but I'm really trying my best. Thanks
1 solutions

Answer 137601 by jim_thompson5910(28476) About Me  on 2009-02-22 20:20:59 (Show Source):
You can put this solution on YOUR website!
Let x=unknown angle
So the supplement is 180-x and the compliment is 90-x

This means that "The measure of the angle's supplement is 40 degrees more than 3 times that of its complement" translates to 180-x=3%2890-x%29%2B40


180-x=3%2890-x%29%2B40 Start with the given equation.


180-x=270-3x%2B40 Distribute.


180-x=-3x%2B310 Combine like terms on the right side.


-x=-3x%2B310-180 Subtract 180 from both sides.


-x%2B3x=310-180 Add 3x to both sides.


2x=310-180 Combine like terms on the left side.


2x=130 Combine like terms on the right side.


x=%28130%29%2F%282%29 Divide both sides by 2 to isolate x.


x=65 Reduce.


----------------------------------------------------------------------

Answer:

So the answer is x=65 which means that the unknown angle is 65 degrees.



Complex_Numbers/183246: 25v^2-9
1 solutions

Answer 137586 by jim_thompson5910(28476) About Me  on 2009-02-22 19:35:41 (Show Source):
You can put this solution on YOUR website!
I'm assuming that you want to factor this.




25v%5E2-9 Start with the given expression.


%285v%29%5E2-9 Rewrite 25v%5E2 as %285v%29%5E2.


%285v%29%5E2-%283%29%5E2 Rewrite 9 as %283%29%5E2.


Notice how we have a difference of squares A%5E2-B%5E2 where in this case A=5v and B=3.


So let's use the difference of squares formula A%5E2-B%5E2=%28A%2BB%29%28A-B%29 to factor the expression:


A%5E2-B%5E2=%28A%2BB%29%28A-B%29 Start with the difference of squares formula.


%285v%29%5E2-%283%29%5E2=%285v%2B3%29%285v-3%29 Plug in A=5v and B=3.


So this shows us that 25v%5E2-9 factors to %285v%2B3%29%285v-3%29.


In other words 25v%5E2-9=%285v%2B3%29%285v-3%29.


Distributive-associative-commutative-properties/183247: 5y^2-28y-12
1 solutions

Answer 137585 by jim_thompson5910(28476) About Me  on 2009-02-22 19:34:28 (Show Source):
You can put this solution on YOUR website!
I'm assuming that you want to factor this.



Looking at the expression 5y%5E2-28y-12, we can see that the first coefficient is 5, the second coefficient is -28, and the last term is -12.


Now multiply the first coefficient 5 by the last term -12 to get %285%29%28-12%29=-60.


Now the question is: what two whole numbers multiply to -60 (the previous product) and add to the second coefficient -28?


To find these two numbers, we need to list all of the factors of -60 (the previous product).


Factors of -60:
1,2,3,4,5,6,10,12,15,20,30,60
-1,-2,-3,-4,-5,-6,-10,-12,-15,-20,-30,-60


Note: list the negative of each factor. This will allow us to find all possible combinations.


These factors pair up and multiply to -60.
1*(-60)
2*(-30)
3*(-20)
4*(-15)
5*(-12)
6*(-10)
(-1)*(60)
(-2)*(30)
(-3)*(20)
(-4)*(15)
(-5)*(12)
(-6)*(10)

Now let's add up each pair of factors to see if one pair adds to the middle coefficient -28:


First NumberSecond NumberSum
1-601+(-60)=-59
2-302+(-30)=-28
3-203+(-20)=-17
4-154+(-15)=-11
5-125+(-12)=-7
6-106+(-10)=-4
-160-1+60=59
-230-2+30=28
-320-3+20=17
-415-4+15=11
-512-5+12=7
-610-6+10=4



From the table, we can see that the two numbers 2 and -30 add to -28 (the middle coefficient).


So the two numbers 2 and -30 both multiply to -60 and add to -28


Now replace the middle term -28y with 2y-30y. Remember, 2 and -30 add to -28. So this shows us that 2y-30y=-28y.


5y%5E2%2Bhighlight%282y-30y%29-12 Replace the second term -28y with 2y-30y.


%285y%5E2%2B2y%29%2B%28-30y-12%29 Group the terms into two pairs.


y%285y%2B2%29%2B%28-30y-12%29 Factor out the GCF y from the first group.


y%285y%2B2%29-6%285y%2B2%29 Factor out 6 from the second group. The goal of this step is to make the terms in the second parenthesis equal to the terms in the first parenthesis.


%28y-6%29%285y%2B2%29 Combine like terms. Or factor out the common term 5y%2B2

---------------------------------------------


Answer:


So 5y%5E2-28y-12 factors to %28y-6%29%285y%2B2%29.


In other words, 5y%5E2-28y-12=%28y-6%29%285y%2B2%29.


Note: you can check the answer by FOILing %28y-6%29%285y%2B2%29 to get 5y%5E2-28y-12 or by graphing the original expression and the answer (the two graphs should be identical).


Distributive-associative-commutative-properties/183250: w^2+14w+49
1 solutions

Answer 137584 by jim_thompson5910(28476) About Me  on 2009-02-22 19:33:16 (Show Source):
You can put this solution on YOUR website!
I'm assuming that you want to factor this.




Looking at the expression w%5E2%2B14w%2B49, we can see that the first coefficient is 1, the second coefficient is 14, and the last term is 49.


Now multiply the first coefficient 1 by the last term 49 to get %281%29%2849%29=49.


Now the question is: what two whole numbers multiply to 49 (the previous product) and add to the second coefficient 14?


To find these two numbers, we need to list all of the factors of 49 (the previous product).


Factors of 49:
1,7,49
-1,-7,-49


Note: list the negative of each factor. This will allow us to find all possible combinations.


These factors pair up and multiply to 49.
1*49
7*7
(-1)*(-49)
(-7)*(-7)

Now let's add up each pair of factors to see if one pair adds to the middle coefficient 14:


First NumberSecond NumberSum
1491+49=50
777+7=14
-1-49-1+(-49)=-50
-7-7-7+(-7)=-14



From the table, we can see that the two numbers 7 and 7 add to 14 (the middle coefficient).


So the two numbers 7 and 7 both multiply to 49 and add to 14


Now replace the middle term 14w with 7w%2B7w. Remember, 7 and 7 add to 14. So this shows us that 7w%2B7w=14w.


w%5E2%2Bhighlight%287w%2B7w%29%2B49 Replace the second term 14w with 7w%2B7w.


%28w%5E2%2B7w%29%2B%287w%2B49%29 Group the terms into two pairs.


w%28w%2B7%29%2B%287w%2B49%29 Factor out the GCF w from the first group.


w%28w%2B7%29%2B7%28w%2B7%29 Factor out 7 from the second group. The goal of this step is to make the terms in the second parenthesis equal to the terms in the first parenthesis.


%28w%2B7%29%28w%2B7%29 Combine like terms. Or factor out the common term w%2B7


%28w%2B7%29%5E2 Condense the factors

---------------------------------------------


Answer:


So w%5E2%2B14w%2B49 factors to %28w%2B7%29%5E2.


In other words, w%5E2%2B14w%2B49=%28w%2B7%29%5E2


Note: you can check the answer by FOILing %28w%2B7%29%28w%2B7%29 to get w%5E2%2B14w%2B49 or by graphing the original expression and the answer (the two graphs should be identical).


Complex_Numbers/183249: 3x^2-4x-4
1 solutions

Answer 137583 by jim_thompson5910(28476) About Me  on 2009-02-22 19:31:49 (Show Source):
You can put this solution on YOUR website!
I'm assuming that you want to factor this.



Looking at the expression 3x%5E2-4x-4, we can see that the first coefficient is 3, the second coefficient is -4, and the last term is -4.


Now multiply the first coefficient 3 by the last term -4 to get %283%29%28-4%29=-12.


Now the question is: what two whole numbers multiply to -12 (the previous product) and add to the second coefficient -4?


To find these two numbers, we need to list all of the factors of -12 (the previous product).


Factors of -12:
1,2,3,4,6,12
-1,-2,-3,-4,-6,-12


Note: list the negative of each factor. This will allow us to find all possible combinations.


These factors pair up and multiply to -12.
1*(-12)
2*(-6)
3*(-4)
(-1)*(12)
(-2)*(6)
(-3)*(4)

Now let's add up each pair of factors to see if one pair adds to the middle coefficient -4:


First NumberSecond NumberSum
1-121+(-12)=-11
2-62+(-6)=-4
3-43+(-4)=-1
-112-1+12=11
-26-2+6=4
-34-3+4=1



From the table, we can see that the two numbers 2 and -6 add to -4 (the middle coefficient).


So the two numbers 2 and -6 both multiply to -12 and add to -4


Now replace the middle term -4x with 2x-6x. Remember, 2 and -6 add to -4. So this shows us that 2x-6x=-4x.


3x%5E2%2Bhighlight%282x-6x%29-4 Replace the second term -4x with 2x-6x.


%283x%5E2%2B2x%29%2B%28-6x-4%29 Group the terms into two pairs.


x%283x%2B2%29%2B%28-6x-4%29 Factor out the GCF x from the first group.


x%283x%2B2%29-2%283x%2B2%29 Factor out 2 from the second group. The goal of this step is to make the terms in the second parenthesis equal to the terms in the first parenthesis.


%28x-2%29%283x%2B2%29 Combine like terms. Or factor out the common term 3x%2B2

---------------------------------------------


Answer:


So 3x%5E2-4x-4 factors to %28x-2%29%283x%2B2%29.


Note: you can check the answer by FOILing %28x-2%29%283x%2B2%29 to get 3x%5E2-4x-4 or by graphing the original expression and the answer (the two graphs should be identical).


Complex_Numbers/183248: z^2-10z-24
1 solutions

Answer 137582 by jim_thompson5910(28476) About Me  on 2009-02-22 19:31:07 (Show Source):
You can put this solution on YOUR website!
I'm assuming that you want to factor this.




Looking at the expression z%5E2-10z-24, we can see that the first coefficient is 1, the second coefficient is -10, and the last term is -24.


Now multiply the first coefficient 1 by the last term -24 to get %281%29%28-24%29=-24.


Now the question is: what two whole numbers multiply to -24 (the previous product) and add to the second coefficient -10?


To find these two numbers, we need to list all of the factors of -24 (the previous product).


Factors of -24:
1,2,3,4,6,8,12,24
-1,-2,-3,-4,-6,-8,-12,-24


Note: list the negative of each factor. This will allow us to find all possible combinations.


These factors pair up and multiply to -24.
1*(-24)
2*(-12)
3*(-8)
4*(-6)
(-1)*(24)
(-2)*(12)
(-3)*(8)
(-4)*(6)

Now let's add up each pair of factors to see if one pair adds to the middle coefficient -10:


First NumberSecond NumberSum
1-241+(-24)=-23
2-122+(-12)=-10
3-83+(-8)=-5
4-64+(-6)=-2
-124-1+24=23
-212-2+12=10
-38-3+8=5
-46-4+6=2



From the table, we can see that the two numbers 2 and -12 add to -10 (the middle coefficient).


So the two numbers 2 and -12 both multiply to -24 and add to -10


Now replace the middle term -10z with 2z-12z. Remember, 2 and -12 add to -10. So this shows us that 2z-12z=-10z.


z%5E2%2Bhighlight%282z-12z%29-24 Replace the second term -10z with 2z-12z.


%28z%5E2%2B2z%29%2B%28-12z-24%29 Group the terms into two pairs.


z%28z%2B2%29%2B%28-12z-24%29 Factor out the GCF z from the first group.


z%28z%2B2%29-12%28z%2B2%29 Factor out 12 from the second group. The goal of this step is to make the terms in the second parenthesis equal to the terms in the first parenthesis.


%28z-12%29%28z%2B2%29 Combine like terms. Or factor out the common term z%2B2

---------------------------------------------


Answer:


So z%5E2-10z-24 factors to %28z-12%29%28z%2B2%29.


Note: you can check the answer by FOILing %28z-12%29%28z%2B2%29 to get z%5E2-10z-24 or by graphing the original expression and the answer (the two graphs should be identical).


Linear-systems/183235: 4c+3d=-2
8c-2d=12
1 solutions

Answer 137580 by jim_thompson5910(28476) About Me  on 2009-02-22 18:51:14 (Show Source):
You can put this solution on YOUR website!

Start with the given system of equations:
system%284c%2B3d=-2%2C8c-2d=12%29


-2%284c%2B3d%29=-2%28-2%29 Multiply the both sides of the first equation by -2.


-8c-6d=4 Distribute and multiply.


So we have the new system of equations:
system%28-8c-6d=4%2C8c-2d=12%29


Now add the equations together. You can do this by simply adding the two left sides and the two right sides separately like this:


%28-8c-6d%29%2B%288c-2d%29=%284%29%2B%2812%29


%28-8c%2B8c%29%2B%28-6d%2B-2d%29=4%2B12 Group like terms.


0c%2B-8d=16 Combine like terms.


-8d=16 Simplify.


d=%2816%29%2F%28-8%29 Divide both sides by -8 to isolate d.


d=-2 Reduce.


------------------------------------------------------------------


-8c-6d=4 Now go back to the first equation.


-8c-6%28-2%29=4 Plug in d=-2.


-8c%2B12=4 Multiply.


-8c=4-12 Subtract 12 from both sides.


-8c=-8 Combine like terms on the right side.


c=%28-8%29%2F%28-8%29 Divide both sides by -8 to isolate c.


c=1 Reduce.


So our answers are c=1 and d=-2.


This means that the system is consistent and independent.


Rational-functions/183233: This question is from textbook Intermediate algebra
6x^2-11x-10/2x^2-9x+10
1 solutions

Answer 137578 by jim_thompson5910(28476) About Me  on 2009-02-22 18:38:17 (Show Source):
You can put this solution on YOUR website!

%286x%5E2-11x-10%29%2F%282x%5E2-9x%2B10%29 Start with the given expression.


%28%283x%2B2%29%282x-5%29%29%2F%282x%5E2-9x%2B10%29 Factor 6x%5E2-11x-10 to get %283x%2B2%29%282x-5%29.


%28%283x%2B2%29%282x-5%29%29%2F%28%28x-2%29%282x-5%29%29 Factor 2x%5E2-9x%2B10 to get %28x-2%29%282x-5%29.


%28%283x%2B2%29highlight%28%282x-5%29%29%29%2F%28%28x-2%29highlight%28%282x-5%29%29%29 Highlight the common terms.


%28%283x%2B2%29cross%28%282x-5%29%29%29%2F%28%28x-2%29cross%28%282x-5%29%29%29 Cancel out the common terms.


%283x%2B2%29%2F%28x-2%29 Simplify.


So %286x%5E2-11x-10%29%2F%282x%5E2-9x%2B10%29 simplifies to %283x%2B2%29%2F%28x-2%29.


In other words, %286x%5E2-11x-10%29%2F%282x%5E2-9x%2B10%29=%283x%2B2%29%2F%28x-2%29 where x%3C%3E-5%2F2 or x%3C%3E2


Percentage-and-ratio-word-problems/183221: What is 5/15 as a percentage?
1 solutions

Answer 137571 by jim_thompson5910(28476) About Me  on 2009-02-22 17:56:15 (Show Source):
You can put this solution on YOUR website!
5%2F15=1%2F3=0.3333 note: the '3's after the decimal repeat forever.


Now multiply by 100 to get 33.33%

So 5%2F15 as a percentage is


Quadratic_Equations/183220: The yellow bus stops at a bus stop every 15 minutes. The blue bus stop at the same bus stop every 20 minutes. If both buses reach the bus stop at 8:30 a.m., what is the next time both the yellow and blue buses will reach the bus stop at the same time?
1 solutions

Answer 137569 by jim_thompson5910(28476) About Me  on 2009-02-22 17:53:17 (Show Source):
You can put this solution on YOUR website!
Since the LCM of 15 and 20 is 60, this means that it will take 60 minutes (1 hour) for the buses to meet at the same time again. So an hour from 8:30 a.m. is 9:30 a.m.

So the buses will meet at 9:30 a.m.


Here's a table to confirm the answer:

Yellow  |  Blue
-----------------
8:30    |  8:30
8:45    |  8:50
9:00    |  9:10
9:15    |  9:30
9:30    |




Exponents-negative-and-fractional/183223: Exponents:
Simplify the expression if possible. Write your answer as a power.
(-2x)4th power

1 solutions

Answer 137567 by jim_thompson5910(28476) About Me  on 2009-02-22 17:41:38 (Show Source):


Exponents/183219: (3z^4 - 8)^2
1 solutions

Answer 137566 by jim_thompson5910(28476) About Me  on 2009-02-22 17:39:45 (Show Source):
You can put this solution on YOUR website!

%283z%5E4-8%29%5E2 Start with the given expression.


%283z%5E4-8%29%283z%5E4-8%29 Expand. Remember something like x%5E2=x%2Ax.


Now let's FOIL the expression.


Remember, when you FOIL an expression, you follow this procedure:


%28highlight%283z%5E4%29-8%29%28highlight%283z%5E4%29-8%29 Multiply the First terms:%283%2Az%5E4%29%2A%283%2Az%5E4%29=9%2Az%5E8.


%28highlight%283z%5E4%29-8%29%283z%5E4%2Bhighlight%28-8%29%29 Multiply the Outer terms:%283%2Az%5E4%29%2A%28-8%29=-24%2Az%5E4.


%283z%5E4%2Bhighlight%28-8%29%29%28highlight%283z%5E4%29-8%29 Multiply the Inner terms:%28-8%29%2A%283%2Az%5E4%29=-24%2Az%5E4.


%283z%5E4%2Bhighlight%28-8%29%29%283z%5E4%2Bhighlight%28-8%29%29 Multiply the Last terms:%28-8%29%2A%28-8%29=64.


---------------------------------------------------
So we have the terms: 9%2Az%5E8, -24%2Az%5E4, -24%2Az%5E4, and 64


9%2Az%5E8-24%2Az%5E4-24%2Az%5E4%2B64 Now collect every term listed above to make a single expression.


9%2Az%5E8-48%2Az%5E4%2B64 Now combine like terms.


So %283z%5E4-8%29%5E2 FOILs to 9%2Az%5E8-48%2Az%5E4%2B64.


In other words, %283z%5E4-8%29%5E2=9%2Az%5E8-48%2Az%5E4%2B64.


Linear-equations/183218: This problem has more than one part, please HELP ME put it all together.?
The price of unleaded regular gasoline varies with the price per barrel of oil on the world market. When oil was selling for $30 per barrel I paid $1.25 per gallon for gasoline. When oil was selling for $140 per barrel, I paid $4.00 for a gallon of gasoline. I have to make a table showing the above data for gasoline and oil prices. Then, I have to construct a graph with oil price per barrel on the horizontal axis and the price per gallon of gasoline on the vertical axis, then plot the two points given and draw a line connecting the two points and extending over the range of $0 to $150 for the price of a barrel of oil, and find the slope of the line, then find the “y” intercept for the line (the point where oil is $0.00 per barrel) and finally write the equation of the line. Assuming that the relationship is linear, I have to calculate the price for a gallon of gasoline when the oil price reaches $39.34 per barrel. How does this compare to the price you are paying today?

1 solutions

Answer 137565 by jim_thompson5910(28476) About Me  on 2009-02-22 17:37:53 (Show Source):
You can put this solution on YOUR website!
Let x=price per barrel of oil and y=price per gallon of gasoline


First translation: "When oil was selling for $30 per barrel I paid $1.25 per gallon for gasoline" means that when x=130, y=1.25. So we have one point (130,1.25)


Second translation: "When oil was selling for $140 per barrel, I paid $4.00 for a gallon of gasoline" means that when x=140, y=4. So we have another point (140,4)


So here's the table of the two ordered pairs (points)
xy
1301.25
1404


Now set up the axis (with the proper ranges and labels)




Plot the two points



Draw a line through the points (in blue)



-----------------------------------------------------------------

Now let's find the equation of the line that goes through the points (130,1.25) and (140,4)



First let's find the slope of the line through the points (130,1.25) and (140,4)


Note: is the first point (130,1.25) and is the second point (140,4)
m=%28y%5B2%5D-y%5B1%5D%29%2F%28x%5B2%5D-x%5B1%5D%29 Start with the slope formula.


m=%284-1.25%29%2F%28140-130%29 Plug in y%5B2%5D=4, y%5B1%5D=1.25, x%5B2%5D=140, and x%5B1%5D=130


m=%282.75%29%2F%28140-130%29 Subtract 1.25 from 4 to get 2.75


m=%282.75%29%2F%2810%29 Subtract 130 from 140 to get 10


m=0.275 Divide

So the slope of the line that goes through the points (130,1.25) and (140,4) is m=0.275


Now let's use the point slope formula:


y-y%5B1%5D=m%28x-x%5B1%5D%29 Start with the point slope formula


y-1.25=0.275%28x-130%29 Plug in m=0.275, x%5B1%5D=130, and y%5B1%5D=1.25


y-1.25=0.275x%2B0.275%28-130%29 Distribute


y-1.25=0.275x-35.75 Multiply


y=0.275x-35.75%2B1.25 Add 1.25 to both sides.


y=0.275x-34.5 Combine like terms.


So the equation that goes through the points (130,1.25) and (140,4) is y=0.275x-34.5


The equation is now in slope intercept form y=mx%2Bb where the slope is m=0.275 and the y-intercept is b=-34.5



Note:
Since the slope is m=0.275, this means that for every dollar increase that the price per barrel of oil experiences, the price per gallon of gas will increase $0.275
Also, the y-intercept is the value when the price of oil is $0 per barrel. So if the price per barrel is $0, then the price of gas is -34.50 dollars.






-------------------------------------------------------------------

"Assuming that the relationship is linear, I have to calculate the price for a gallon of gasoline when the oil price reaches $39.34 per barrel"


In this case, we want to know "y" when "x" is equal to 39.34. So simply plug in x=39.34 to find "y"

y=0.275x-34.5 Start with the equation we just found


y=0.275%2839.34%29-34.5 Plug in x=39.34


y=10.8185-34.5 Multiply


y=-23.6815 Subtract


So when the price of oil is $39.34 a barrel, the price of gas will be about -23.68 dollars a barrel.


Note: the relationship between the price of oil and the price of gas is a little more complex than just a simple linear relationship (since there are more factors involved).


Equations/183211: "find all integers m for which y^2+my+50 can be factored?"
1 solutions

Answer 137556 by jim_thompson5910(28476) About Me  on 2009-02-22 16:26:52 (Show Source):
You can put this solution on YOUR website!
First, multiply the first coefficient 1 and the last term 50 to get 50. Now list the factors of 50




Factors of 50:
1,2,5,10,25,50
-1,-2,-5,-10,-25,-50


Note: list the negative of each factor. This will allow us to find all possible combinations.


These factors pair up and multiply to 50.
1*50
2*25
5*10
(-1)*(-50)
(-2)*(-25)
(-5)*(-10)

Now add up each paired factor (ie 1+50=51, 2+25=27, etc..):


First NumberSecond NumberSum
1501+50=51
2252+25=27
5105+10=15
-1-50-1+(-50)=-51
-2-25-2+(-25)=-27
-5-10-5+(-10)=-15



All of the numbers in the last column are possible values for the value of "m". Remember, you can only factor ax%5E2%2Bbx%2Bc only if the factors of ac add to "b"


So the possible values for "m" are: 51, 27, 15, -51, -27, -15


Note: all of these values of "m" are straight from that third column.


This means that the following quadratics are factorable:

y%5E2%2B51y%2B50,

y%5E2%2B27y%2B50,

y%5E2%2B15y%2B50,

y%5E2-51y%2B50,

y%5E2-27y%2B50, and

y%5E2-15y%2B50


real-numbers/183200: "suppose x^2+a^2x+a^2 factors into (x+a)^2. what is the value of a, that is not zero?"
1 solutions

Answer 137554 by jim_thompson5910(28476) About Me  on 2009-02-22 16:07:12 (Show Source):
You can put this solution on YOUR website!
Since we're supposing that "x^2+a^2x+a^2 factors into (x+a)^2", this means that

x%5E2%2Ba%5E2x%2Ba%5E2=%28x%2Ba%29%5E2


x%5E2%2Ba%5E2x%2Ba%5E2=%28x%2Ba%29%5E2 Start with the given equation.


x%5E2%2Ba%5E2x%2Ba%5E2=x%5E2%2B2ax%2Ba%5E2 FOIL the right side


cross%28x%5E2-x%5E2%29%2Ba%5E2x%2Ba%5E2=cross%28x%5E2-x%5E2%29%2B2ax%2Ba%5E2 Subtract x%5E2 from both sides. Note: the x%5E2 terms cancel out.


a%5E2x%2Bcross%28a%5E2-a%5E2%29=2ax%2Bcross%28a%5E2-a%5E2%29 Subtract a%5E2 from both sides. Note: the a%5E2 terms cancel out.


So we're left with:

a%5E2x=2ax


%28a%5E2%2Across%28x%29%29%2Fcross%28x%29=%282a%2Across%28x%29%29%2Fcross%28x%29 Divide both sides by "x". Once again, the "x" terms cancel


a%5E2=2a Simplify


a%5E2-2a=0 Subtract 2a from both sides.




a%28a-2%29=0 Factor the left side


Now set each factor equal to zero:

a=0 or a-2=0


a=0 or a=2 Now solve for "a" in each case


Note: since we want a value of "a" "that is not zero", this means that we'll ignore the value a=0

===========================================================

Answer:

So the solution is a=2


Quadratic-relations-and-conic-sections/183194: Given that the equation of a circle is x^2+y^2-10x+4y+13=0, find its center and its radius.
1 solutions

Answer 137551 by jim_thompson5910(28476) About Me  on 2009-02-22 15:51:34 (Show Source):
You can put this solution on YOUR website!
x%5E2%2By%5E2-10x%2B4y%2B13=0 Start with the given equation.


x%5E2%2By%5E2-10x%2B4y=-13 Subtract 13 from both sides.


%28x%5E2-10x%29%2B%28y%5E2%2B4y%29=-13 Group like terms.


%28x%5E2-10x%2Bhighlight%2825%29%29%2B%28y%5E2%2B4y%29=-13%2Bhighlight%2825%29 Take half of the "x" coefficient -10 to get -5. Square it to get 25. Add this to both sides.


%28x%5E2-10x%2B25%29%2B%28y%5E2%2B4y%2Bhighlight%284%29%29=-13%2B25%2Bhighlight%284%29 Take half of the "y" coefficient 4 to get 2. Square that result to get 4. Add this to both sides.


%28x%5E2-10x%2B25%29%2B%28y%5E2%2B4y%2B4%29=-13%2B25%2B4


%28x%5E2-10x%2B25%29%2B%28y%5E2%2B4y%2B4%29=16 Combine like terms.


%28x-5%29%5E2%2B%28y%5E2%2B4y%2B4%29=16 Factor x%5E2-10x%2B25 to get %28x-5%29%5E2


%28x-5%29%5E2%2B%28y%2B2%29%5E2=16 Factor y%5E2%2B4y%2B4 to get %28y%2B2%29%5E2


%28x-5%29%5E2%2B%28y%2B2%29%5E2=4%5E2 Rewrite 16 as 4%5E2


%28x-5%29%5E2%2B%28y-%28-2%29%29%5E2=4%5E2 Rewrite y%2B2 as y-%28-2%29


So the equation is now in the form %28x-h%29%5E2%2B%28y-k%29%5E2=r%5E2 (which is a circle) where (h,k) is the center and "r" is the radius


We can see that h=5, k=-2, and r=4


So the center is (5,-2) and the radius is 4 units


Rational-functions/183192: What is the equation of the perpendicular bisector of the line between the points (2,2) and (6,6)?
1 solutions

Answer 137550 by jim_thompson5910(28476) About Me  on 2009-02-22 15:42:47 (Show Source):
You can put this solution on YOUR website!
Step 1) First find midpoint of the points (2,2) and (6,6)



To find the midpoint, first we need to find the individual coordinates of the midpoint.


X-Coordinate of the Midpoint:




To find the x-coordinate of the midpoint, simply average the two x-coordinates of the given points by adding them up and dividing that result by 2 like this:


x%5Bmid%5D=%282%2B6%29%2F2=8%2F2=4


So the x-coordinate of the midpoint is x=4


-----------------------------------------------------


Y-Coordinate of the Midpoint:




To find the y-coordinate of the midpoint, simply average the two y-coordinates of the given points by adding them up and dividing that result by 2 like this:


y%5Bmid%5D=%282%2B6%29%2F2=8%2F2=4


So the y-coordinate of the midpoint is y=4


So the midpoint between the points and is



=======================================================


Step 2) Find the slope of the line through the points (2,2) and (6,6)




Note: is the first point and is the second point .


m=%28y%5B2%5D-y%5B1%5D%29%2F%28x%5B2%5D-x%5B1%5D%29 Start with the slope formula.


m=%286-2%29%2F%286-2%29 Plug in y%5B2%5D=6, y%5B1%5D=2, x%5B2%5D=6, and x%5B1%5D=2


m=%284%29%2F%286-2%29 Subtract 2 from 6 to get 4


m=%284%29%2F%284%29 Subtract 2 from 6 to get 4


m=1 Reduce


So the slope of the line that goes through the points and is m=1

==========================================================

Step 3) Find the perpendicular slope

Take the slope m=1 and flip the fraction (think of it as m=1%2F1) to get m=1%2F1 and change the sign to get m=-1%2F1. So the perpendicular slope is m=-1


==========================================================

Step 4) Find the equation of the line with the perpendicular slope (found in step 3) which goes through the midpoint (found in step 1)


To recap, the perpendicular slope is m=-1 and the point that the perpendicular bisector goes through is (4,4)


So let's find the equation of the line with a slope m=-1 and goes through the point (4,4)




If you want to find the equation of line with a given a slope of -1 which goes through the point (4,4), you can simply use the point-slope formula to find the equation:


---Point-Slope Formula---
y-y%5B1%5D=m%28x-x%5B1%5D%29 where m is the slope, and is the given point


So lets use the Point-Slope Formula to find the equation of the line


y-4=%28-1%29%28x-4%29 Plug in m=-1, x%5B1%5D=4, and y%5B1%5D=4 (these values are given)


y-4=-x%2B%28-1%29%28-4%29 Distribute -1


y-4=-x%2B4 Multiply -1 and -4 to get 4


y=-x%2B4%2B4 Add 4 to both sides to isolate y


y=-x%2B8 Combine like terms 4 and 4 to get 8


So the equation of the line with a slope of -1 which goes through the point (4,4) is:


y=-x%2B8 which is now in y=mx%2Bb form where the slope is m=-1 and the y-intercept is b=8



==============================================================

Answer:


So the equation of the perpendicular bisector of the line between the points (2,2) and (6,6) is y=-x%2B8


So the answer you're looking for is y=-x%2B8



Here's the graph to verify the answer:




Rational-functions/183191: Find the coordinates of the point C, halfway between the points A(5,1) and B(-2, 7).
1 solutions

Answer 137548 by jim_thompson5910(28476) About Me  on 2009-02-22 15:31:26 (Show Source):
You can put this solution on YOUR website!

To find the midpoint, first we need to find the individual coordinates of the midpoint.


X-Coordinate of the Midpoint:




To find the x-coordinate of the midpoint, simply average the two x-coordinates of the given points by adding them up and dividing that result by 2 like this:


x%5Bmid%5D=%285%2B-2%29%2F2=3%2F2


So the x-coordinate of the midpoint is x=3%2F2


-----------------------------------------------------


Y-Coordinate of the Midpoint:




To find the y-coordinate of the midpoint, simply average the two y-coordinates of the given points by adding them up and dividing that result by 2 like this:


y%5Bmid%5D=%281%2B7%29%2F2=8%2F2=4


So the y-coordinate of the midpoint is y=4


So the midpoint between the points and is


Linear-equations/183190: Solve 5x + 6y=18 for y
1 solutions

Answer 137545 by jim_thompson5910(28476) About Me  on 2009-02-22 15:21:06 (Show Source):
You can put this solution on YOUR website!
5x%2B6y=18 Start with the given equation.


6y=18-5x Subtract 5x from both sides.


6y=-5x%2B18 Rearrange the terms.


y=%28-5x%2B18%29%2F%286%29 Divide both sides by 6 to isolate y.


y=%28%28-5%29%2F%286%29%29x%2B%2818%29%2F%286%29 Break up the fraction.


y=-%285%2F6%29x%2B3 Reduce.


Expressions-with-variables/183181: expand. (x+y)^6
1 solutions

Answer 137536 by jim_thompson5910(28476) About Me  on 2009-02-22 14:35:18 (Show Source):
You can put this solution on YOUR website!


%28x%2By%29%5E6 Start with the given expression

To expand this, we're going to use binomial expansion. So let's look at Pascal's triangle:
1   

1   1   

1   2   1   

1   3   3   1   

1   4   6   4   1   

1   5   10   10   5   1   

1   6   15   20   15   6   1   




Looking at the row that starts with 1,6, etc, we can see that this row has the numbers:

1, 6, 15, 20, 15, 6, and 1

These numbers will be the coefficients of our expansion. So to expand %28x%2By%29%5E6, simply follow this procedure:
Write the first coefficient. Multiply that coefficient with the first binomial term x and then the second binomial term y. Repeat this until all of the coefficients have been written.

Once that has been done, add up the terms like this:


Notice how the coefficients are in front of each term.



However, we're not done yet.


Looking at the first term 1%28x%29%28y%29, raise x to the 6th power and raise y to the 0th power.

Looking at the second term 6%28x%29%28y%29 raise x to the 5th power and raise y to the 1st power.

Continue this until you reach the final term.


Notice how the exponents of x are stepping down and the exponents of y are stepping up.


So the fully expanded expression should now look like this:





Distribute the exponents


Multiply


x%5E6%2B6x%5E5y%2B15x%5E4y%5E2%2B20x%5E3y%5E3%2B15x%5E2y%5E4%2B6xy%5E5%2By%5E6 Multiply the terms with their coefficients


So %28x%2By%29%5E6 expands and simplifies to x%5E6%2B6x%5E5y%2B15x%5E4y%5E2%2B20x%5E3y%5E3%2B15x%5E2y%5E4%2B6xy%5E5%2By%5E6.


In other words,


Polynomials-and-rational-expressions/183160: This question is from textbook
6g^3-24g^2+24g
1 solutions

Answer 137533 by jim_thompson5910(28476) About Me  on 2009-02-22 13:59:17 (Show Source):
You can put this solution on YOUR website!
I assume that you want to factor right? Please post full instructions.



6g%5E3-24g%5E2%2B24g Start with the given expression


6g%28g%5E2-4g%2B4%29 Factor out the GCF 6g


Now let's focus on the inner expression g%5E2-4g%2B4




------------------------------------------------------------



Looking at 1g%5E2-4g%2B4 we can see that the first term is 1g%5E2 and the last term is 4 where the coefficients are 1 and 4 respectively.

Now multiply the first coefficient 1 and the last coefficient 4 to get 4. Now what two numbers multiply to 4 and add to the middle coefficient -4? Let's list all of the factors of 4:



Factors of 4:
1,2

-1,-2 ...List the negative factors as well. This will allow us to find all possible combinations

These factors pair up and multiply to 4
1*4
2*2
(-1)*(-4)
(-2)*(-2)

note: remember two negative numbers multiplied together make a positive number


Now which of these pairs add to -4? Lets make a table of all of the pairs of factors we multiplied and see which two numbers add to -4

First NumberSecond NumberSum
141+4=5
222+2=4
-1-4-1+(-4)=-5
-2-2-2+(-2)=-4



From this list we can see that -2 and -2 add up to -4 and multiply to 4


Now looking at the expression 1g%5E2-4g%2B4, replace -4g with -2g%2B-2g (notice -2g%2B-2g adds up to -4g. So it is equivalent to -4g)

1g%5E2%2Bhighlight%28-2g%2B-2g%29%2B4


Now let's factor 1g%5E2-2g-2g%2B4 by grouping:


%281g%5E2-2g%29%2B%28-2g%2B4%29 Group like terms


g%28g-2%29-2%28g-2%29 Factor out the GCF of g out of the first group. Factor out the GCF of -2 out of the second group


%28g-2%29%28g-2%29 Since we have a common term of g-2, we can combine like terms

So 1g%5E2-2g-2g%2B4 factors to %28g-2%29%28g-2%29


So this also means that 1g%5E2-4g%2B4 factors to %28g-2%29%28g-2%29 (since 1g%5E2-4g%2B4 is equivalent to 1g%5E2-2g-2g%2B4)


note: %28g-2%29%28g-2%29 is equivalent to %28g-2%29%5E2 since the term g-2 occurs twice. So 1g%5E2-4g%2B4 also factors to %28g-2%29%5E2



------------------------------------------------------------




So our expression goes from 6g%28g%5E2-4g%2B4%29 and factors further to 6g%28g-2%29%5E2


------------------
Answer:

So 6g%5E3-24g%5E2%2B24g factors to 6g%28g-2%29%5E2


Distributive-associative-commutative-properties/183091: 81x^4-16
1 solutions

Answer 137483 by jim_thompson5910(28476) About Me  on 2009-02-21 23:42:41 (Show Source):
You can put this solution on YOUR website!

81x%5E4-16 Start with the given expression.


%289x%5E2%29%5E2-16 Rewrite 81x%5E4 as %289x%5E2%29%5E2.


%289x%5E2%29%5E2-%284%29%5E2 Rewrite 16 as %284%29%5E2.


Notice how we have a difference of squares A%5E2-B%5E2 where in this case A=9x%5E2 and B=4.


So let's use the difference of squares formula A%5E2-B%5E2=%28A%2BB%29%28A-B%29 to factor the expression:


A%5E2-B%5E2=%28A%2BB%29%28A-B%29 Start with the difference of squares formula.


%289x%5E2%29%5E2-%284%29%5E2=%289x%5E2%2B4%29%289x%5E2-4%29 Plug in A=9x%5E2 and B=4.


So this shows us that 81x%5E4-16 factors to %289x%5E2%2B4%29%289x%5E2-4%29.


In other words 81x%5E4-16=%289x%5E2%2B4%29%289x%5E2-4%29.



Now let's factor 9x%5E2-4 further

-------------------------------------


9x%5E2-4 Start with the given expression.


%283x%29%5E2-4 Rewrite 9x%5E2 as %283x%29%5E2.


%283x%29%5E2-%282%29%5E2 Rewrite 4 as %282%29%5E2.


Notice how we have a difference of squares A%5E2-B%5E2 where in this case A=3x and B=2.


So let's use the difference of squares formula A%5E2-B%5E2=%28A%2BB%29%28A-B%29 to factor the expression:


A%5E2-B%5E2=%28A%2BB%29%28A-B%29 Start with the difference of squares formula.


%283x%29%5E2-%282%29%5E2=%283x%2B2%29%283x-2%29 Plug in A=3x and B=2.


So this shows us that 9x%5E2-4 factors to %283x%2B2%29%283x-2%29.


In other words 9x%5E2-4=%283x%2B2%29%283x-2%29.

----------------------------------------------------------------

Answer:


So 81x%5E4-16 completely factors to %289x%5E2%2B4%29%283x%2B2%29%283x-2%29


Distributive-associative-commutative-properties/183092: 36x²+12xy+y²
1 solutions

Answer 137482 by jim_thompson5910(28476) About Me  on 2009-02-21 23:40:03 (Show Source):
You can put this solution on YOUR website!
I assume that you want to factor.




Looking at 36x%5E2%2B12xy%2By%5E2 we can see that the first term is 36x%5E2 and the last term is y%5E2 where the coefficients are 36 and 1 respectively.

Now multiply the first coefficient 36 and the last coefficient 1 to get 36. Now what two numbers multiply to 36 and add to the middle coefficient 12? Let's list all of the factors of 36:



Factors of 36:
1,2,3,4,6,9,12,18

-1,-2,-3,-4,-6,-9,-12,-18 ...List the negative factors as well. This will allow us to find all possible combinations

These factors pair up and multiply to 36
1*36
2*18
3*12
4*9
6*6
(-1)*(-36)
(-2)*(-18)
(-3)*(-12)
(-4)*(-9)
(-6)*(-6)

note: remember two negative numbers multiplied together make a positive number


Now which of these pairs add to 12? Lets make a table of all of the pairs of factors we multiplied and see which two numbers add to 12

First NumberSecond NumberSum
1361+36=37
2182+18=20
3123+12=15
494+9=13
666+6=12
-1-36-1+(-36)=-37
-2-18-2+(-18)=-20
-3-12-3+(-12)=-15
-4-9-4+(-9)=-13
-6-6-6+(-6)=-12



From this list we can see that 6 and 6 add up to 12 and multiply to 36


Now looking at the expression 36x%5E2%2B12xy%2By%5E2, replace 12xy with 6xy%2B6xy (notice 6xy%2B6xy adds up to 12xy. So it is equivalent to 12xy)

36x%5E2%2Bhighlight%286xy%2B6xy%29%2By%5E2


Now let's factor 36x%5E2%2B6xy%2B6xy%2By%5E2 by grouping:


%2836x%5E2%2B6xy%29%2B%286xy%2By%5E2%29 Group like terms


6x%286x%2By%29%2By%286x%2By%29 Factor out the GCF of 6x out of the first group. Factor out the GCF of y out of the second group


%286x%2By%29%286x%2By%29 Since we have a common term of 6x%2By, we can combine like terms

So 36x%5E2%2B6xy%2B6xy%2By%5E2 factors to %286x%2By%29%286x%2By%29


So this also means that 36x%5E2%2B12xy%2By%5E2 factors to %286x%2By%29%286x%2By%29 (since 36x%5E2%2B12xy%2By%5E2 is equivalent to 36x%5E2%2B6xy%2B6xy%2By%5E2)


note: %286x%2By%29%286x%2By%29 is equivalent to %286x%2By%29%5E2 since the term 6x%2By occurs twice. So 36x%5E2%2B12xy%2By%5E2 also factors to %286x%2By%29%5E2



------------------------------------------------------------



Answer:
So 36x%5E2%2B12xy%2By%5E2 factors to %286x%2By%29%5E2


Quadratic_Equations/183093: 2x²-x=15
1 solutions

Answer 137481 by jim_thompson5910(28476) About Me  on 2009-02-21 23:37:41 (Show Source):
You can put this solution on YOUR website!

2x%5E2-x=15 Start with the given equation.


2x%5E2-x-15=0 Subtract 15 from both sides.


Notice we have a quadratic equation in the form of ax%5E2%2Bbx%2Bc where a=2, b=-1, and c=-15


Let's use the quadratic formula to solve for x


x+=+%28-b+%2B-+sqrt%28+b%5E2-4ac+%29%29%2F%282a%29 Start with the quadratic formula


x+=+%28-%28-1%29+%2B-+sqrt%28+%28-1%29%5E2-4%282%29%28-15%29+%29%29%2F%282%282%29%29 Plug in a=2, b=-1, and c=-15


x+=+%281+%2B-+sqrt%28+%28-1%29%5E2-4%282%29%28-15%29+%29%29%2F%282%282%29%29 Negate -1 to get 1.


x+=+%281+%2B-+sqrt%28+1-4%282%29%28-15%29+%29%29%2F%282%282%29%29 Square -1 to get 1.


x+=+%281+%2B-+sqrt%28+1--120+%29%29%2F%282%282%29%29 Multiply 4%282%29%28-15%29 to get -120


x+=+%281+%2B-+sqrt%28+1%2B120+%29%29%2F%282%282%29%29 Rewrite sqrt%281--120%29 as sqrt%281%2B120%29


x+=+%281+%2B-+sqrt%28+121+%29%29%2F%282%282%29%29 Add 1 to 120 to get 121


x+=+%281+%2B-+sqrt%28+121+%29%29%2F%284%29 Multiply 2 and 2 to get 4.


x+=+%281+%2B-+11%29%2F%284%29 Take the square root of 121 to get 11.


x+=+%281+%2B+11%29%2F%284%29 or x+=+%281+-+11%29%2F%284%29 Break up the expression.


x+=+%2812%29%2F%284%29 or x+=++%28-10%29%2F%284%29 Combine like terms.


x+=+3 or x+=+-5%2F2 Simplify.


So the answers are x+=+3 or x+=+-5%2F2