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Expressions-with-variables/119604: This question is from textbook glenco mathmatics
2x- y = -4
-3x + y = -9
1 solutions

Answer 87727 by jim_thompson5910(28504) About Me  on 2008-01-11 19:13:18 (Show Source):
You can put this solution on YOUR website!
Solved by pluggable solver: Solving a linear system of equations by subsitution


Lets start with the given system of linear equations

2%2Ax-1%2Ay=-4
-3%2Ax%2B1%2Ay=-9

Now in order to solve this system by using substitution, we need to solve (or isolate) one variable. I'm going to choose y.

Solve for y for the first equation

-1%2Ay=-4-2%2AxSubtract 2%2Ax from both sides

y=%28-4-2%2Ax%29%2F-1 Divide both sides by -1.


Which breaks down and reduces to



y=4%2B2%2Ax Now we've fully isolated y

Since y equals 4%2B2%2Ax we can substitute the expression 4%2B2%2Ax into y of the 2nd equation. This will eliminate y so we can solve for x.


-3%2Ax%2B1%2Ahighlight%28%284%2B2%2Ax%29%29=-9 Replace y with 4%2B2%2Ax. Since this eliminates y, we can now solve for x.

-3%2Ax%2B1%2A%284%29%2B1%282%29x=-9 Distribute 1 to 4%2B2%2Ax

-3%2Ax%2B4%2B2%2Ax=-9 Multiply



-3%2Ax%2B4%2B2%2Ax=-9 Reduce any fractions

-3%2Ax%2B2%2Ax=-9-4 Subtract 4 from both sides


-3%2Ax%2B2%2Ax=-13 Combine the terms on the right side



-1%2Ax=-13 Now combine the terms on the left side.


cross%28%281%2F-1%29%28-1%2F1%29%29x=%28-13%2F1%29%281%2F-1%29 Multiply both sides by 1%2F-1. This will cancel out -1%2F1 and isolate x

So when we multiply -13%2F1 and 1%2F-1 (and simplify) we get



x=13 <---------------------------------One answer

Now that we know that x=13, lets substitute that in for x to solve for y

-3%2813%29%2B1%2Ay=-9 Plug in x=13 into the 2nd equation

-39%2B1%2Ay=-9 Multiply

1%2Ay=-9%2B39Add 39 to both sides

1%2Ay=30 Combine the terms on the right side

cross%28%281%2F1%29%281%29%29%2Ay=%2830%2F1%29%281%2F1%29 Multiply both sides by 1%2F1. This will cancel out 1 on the left side.

y=30%2F1 Multiply the terms on the right side


y=30 Reduce


So this is the other answer


y=30<---------------------------------Other answer


So our solution is

x=13 and y=30

which can also look like

(13,30)

Notice if we graph the equations (if you need help with graphing, check out this solver)

2%2Ax-1%2Ay=-4
-3%2Ax%2B1%2Ay=-9

we get


graph of 2%2Ax-1%2Ay=-4 (red) and -3%2Ax%2B1%2Ay=-9 (green) (hint: you may have to solve for y to graph these) intersecting at the blue circle.


and we can see that the two equations intersect at (13,30). This verifies our answer.


-----------------------------------------------------------------------------------------------
Check:

Plug in (13,30) into the system of equations


Let x=13 and y=30. Now plug those values into the equation 2%2Ax-1%2Ay=-4

2%2A%2813%29-1%2A%2830%29=-4 Plug in x=13 and y=30


26-30=-4 Multiply


-4=-4 Add


-4=-4 Reduce. Since this equation is true the solution works.


So the solution (13,30) satisfies 2%2Ax-1%2Ay=-4



Let x=13 and y=30. Now plug those values into the equation -3%2Ax%2B1%2Ay=-9

-3%2A%2813%29%2B1%2A%2830%29=-9 Plug in x=13 and y=30


-39%2B30=-9 Multiply


-9=-9 Add


-9=-9 Reduce. Since this equation is true the solution works.


So the solution (13,30) satisfies -3%2Ax%2B1%2Ay=-9


Since the solution (13,30) satisfies the system of equations


2%2Ax-1%2Ay=-4
-3%2Ax%2B1%2Ay=-9


this verifies our answer.




Complex_Numbers/119657: 2x + y = 3 with no given numbers
1 solutions

Answer 87726 by jim_thompson5910(28504) About Me  on 2008-01-11 19:11:41 (Show Source):
You can put this solution on YOUR website!
Do you want to graph?

Solved by pluggable solver: Graphing Linear Equations


2%2Ax%2B1%2Ay=3Start with the given equation



1%2Ay=3-2%2Ax Subtract 2%2Ax from both sides

y=%281%29%283-2%2Ax%29 Multiply both sides by 1

y=%281%29%283%29-%281%29%282%29x%29 Distribute 1

y=3-%282%29x Multiply

y=-2%2Ax%2B3 Rearrange the terms

y=-2%2Ax%2B3 Reduce any fractions

So the equation is now in slope-intercept form (y=mx%2Bb) where m=-2 (the slope) and b=3 (the y-intercept)

So to graph this equation lets plug in some points

Plug in x=-3

y=-2%2A%28-3%29%2B3

y=6%2B3 Multiply

y=9 Add

So here's one point (-3,9)





Now lets find another point

Plug in x=-2

y=-2%2A%28-2%29%2B3

y=4%2B3 Multiply

y=7 Add

So here's another point (-2,7). Add this to our graph





Now draw a line through these points

So this is the graph of y=-2%2Ax%2B3 through the points (-3,9) and (-2,7)


So from the graph we can see that the slope is -2%2F1 (which tells us that in order to go from point to point we have to start at one point and go down -2 units and to the right 1 units to get to the next point), the y-intercept is (0,3)and the x-intercept is (1.5,0) ,or (3%2F2,0) . So all of this information verifies our graph.


We could graph this equation another way. Since b=3 this tells us that the y-intercept (the point where the graph intersects with the y-axis) is (0,3).


So we have one point (0,3)






Now since the slope is -2%2F1, this means that in order to go from point to point we can use the slope to do so. So starting at (0,3), we can go down 2 units


and to the right 1 units to get to our next point



Now draw a line through those points to graph y=-2%2Ax%2B3


So this is the graph of y=-2%2Ax%2B3 through the points (0,3) and (1,1)


Linear-equations/119723: Graph each equation, 2x - 3y =12
1 solutions

Answer 87723 by jim_thompson5910(28504) About Me  on 2008-01-11 18:32:58 (Show Source):
You can put this solution on YOUR website!
Solved by pluggable solver: Graphing Linear Equations


2%2Ax-3%2Ay=12Start with the given equation



-3%2Ay=12-2%2Ax Subtract 2%2Ax from both sides

y=%28-1%2F3%29%2812-2%2Ax%29 Multiply both sides by -1%2F3

y=%28-1%2F3%29%2812%29%2B%281%2F3%29%282%29x%29 Distribute -1%2F3

y=-12%2F3%2B%282%2F3%29x Multiply

y=%282%2F3%29%2Ax-12%2F3 Rearrange the terms

y=%282%2F3%29%2Ax-4 Reduce any fractions

So the equation is now in slope-intercept form (y=mx%2Bb) where m=2%2F3 (the slope) and b=-4 (the y-intercept)

So to graph this equation lets plug in some points

Plug in x=-6

y=%282%2F3%29%2A%28-6%29-4

y=-12%2F3-4 Multiply

y=-24%2F3 Add

y=-8 Reduce

So here's one point (-6,-8)





Now lets find another point

Plug in x=-3

y=%282%2F3%29%2A%28-3%29-4

y=-6%2F3-4 Multiply

y=-18%2F3 Add

y=-6 Reduce

So here's another point (-3,-6). Add this to our graph





Now draw a line through these points

So this is the graph of y=%282%2F3%29%2Ax-4 through the points (-6,-8) and (-3,-6)


So from the graph we can see that the slope is 2%2F3 (which tells us that in order to go from point to point we have to start at one point and go up 2 units and to the right 3 units to get to the next point) the y-intercept is (0,-4)and the x-intercept is (6,0) . So all of this information verifies our graph.


We could graph this equation another way. Since b=-4 this tells us that the y-intercept (the point where the graph intersects with the y-axis) is (0,-4).


So we have one point (0,-4)






Now since the slope is 2%2F3, this means that in order to go from point to point we can use the slope to do so. So starting at (0,-4), we can go up 2 units


and to the right 3 units to get to our next point



Now draw a line through those points to graph y=%282%2F3%29%2Ax-4


So this is the graph of y=%282%2F3%29%2Ax-4 through the points (0,-4) and (3,-2)


Polynomials-and-rational-expressions/119700: factoring z^2+18z+45
1 solutions

Answer 87711 by jim_thompson5910(28504) About Me  on 2008-01-11 16:03:54 (Show Source):
You can put this solution on YOUR website!

Looking at z%5E2%2B18z%2B45 we can see that the first term is z%5E2 and the last term is 45 where the coefficients are 1 and 45 respectively.

Now multiply the first coefficient 1 and the last coefficient 45 to get 45. Now what two numbers multiply to 45 and add to the middle coefficient 18? Let's list all of the factors of 45:



Factors of 45:
1,3,5,9,15,45

-1,-3,-5,-9,-15,-45 ...List the negative factors as well. This will allow us to find all possible combinations

These factors pair up and multiply to 45
1*45
3*15
5*9
(-1)*(-45)
(-3)*(-15)
(-5)*(-9)

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


Now which of these pairs add to 18? Lets make a table of all of the pairs of factors we multiplied and see which two numbers add to 18

First NumberSecond NumberSum
1451+45=46
3153+15=18
595+9=14
-1-45-1+(-45)=-46
-3-15-3+(-15)=-18
-5-9-5+(-9)=-14



From this list we can see that 3 and 15 add up to 18 and multiply to 45


Now looking at the expression z%5E2%2B18z%2B45, replace 18z with 3z%2B15z (notice 3z%2B15z adds up to 18z. So it is equivalent to 18z)

z%5E2%2Bhighlight%283z%2B15z%29%2B45


Now let's factor z%5E2%2B3z%2B15z%2B45 by grouping:


%28z%5E2%2B3z%29%2B%2815z%2B45%29 Group like terms


z%28z%2B3%29%2B15%28z%2B3%29 Factor out the GCF of z out of the first group. Factor out the GCF of 15 out of the second group


%28z%2B15%29%28z%2B3%29 Since we have a common term of z%2B3, we can combine like terms

So z%5E2%2B3z%2B15z%2B45 factors to %28z%2B15%29%28z%2B3%29


So this also means that z%5E2%2B18z%2B45 factors to %28z%2B15%29%28z%2B3%29 (since z%5E2%2B18z%2B45 is equivalent to z%5E2%2B3z%2B15z%2B45)



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



Answer:
So z%5E2%2B18z%2B45 factors to %28z%2B15%29%28z%2B3%29


Polynomials-and-rational-expressions/119704: Factor completlety 16x^2-2x-3
1 solutions

Answer 87710 by jim_thompson5910(28504) About Me  on 2008-01-11 16:02:07 (Show Source):
You can put this solution on YOUR website!

Looking at 16x%5E2-2x-3 we can see that the first term is 16x%5E2 and the last term is -3 where the coefficients are 16 and -3 respectively.

Now multiply the first coefficient 16 and the last coefficient -3 to get -48. Now what two numbers multiply to -48 and add to the middle coefficient -2? Let's list all of the factors of -48:



Factors of -48:
1,2,3,4,6,8,12,16,24,48

-1,-2,-3,-4,-6,-8,-12,-16,-24,-48 ...List the negative factors as well. This will allow us to find all possible combinations

These factors pair up and multiply to -48
(1)*(-48)
(2)*(-24)
(3)*(-16)
(4)*(-12)
(6)*(-8)
(-1)*(48)
(-2)*(24)
(-3)*(16)
(-4)*(12)
(-6)*(8)

note: remember, the product of a negative and a positive number is a negative 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
1-481+(-48)=-47
2-242+(-24)=-22
3-163+(-16)=-13
4-124+(-12)=-8
6-86+(-8)=-2
-148-1+48=47
-224-2+24=22
-316-3+16=13
-412-4+12=8
-68-6+8=2



From this list we can see that 6 and -8 add up to -2 and multiply to -48


Now looking at the expression 16x%5E2-2x-3, replace -2x with 6x%2B-8x (notice 6x%2B-8x adds up to -2x. So it is equivalent to -2x)

16x%5E2%2Bhighlight%286x%2B-8x%29%2B-3


Now let's factor 16x%5E2%2B6x-8x-3 by grouping:


%2816x%5E2%2B6x%29%2B%28-8x-3%29 Group like terms


2x%288x%2B3%29-1%288x%2B3%29 Factor out the GCF of 2x out of the first group. Factor out the GCF of -1 out of the second group


%282x-1%29%288x%2B3%29 Since we have a common term of 8x%2B3, we can combine like terms

So 16x%5E2%2B6x-8x-3 factors to %282x-1%29%288x%2B3%29


So this also means that 16x%5E2-2x-3 factors to %282x-1%29%288x%2B3%29 (since 16x%5E2-2x-3 is equivalent to 16x%5E2%2B6x-8x-3)



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



Answer:
So 16x%5E2-2x-3 factors to %282x-1%29%288x%2B3%29


expressions/119708: How do I factor this?
X^2-12x+36
1 solutions

Answer 87709 by jim_thompson5910(28504) About Me  on 2008-01-11 16:01:02 (Show Source):
You can put this solution on YOUR website!

Looking at x%5E2-12x%2B36 we can see that the first term is x%5E2 and the last term is 36 where the coefficients are 1 and 36 respectively.

Now multiply the first coefficient 1 and the last coefficient 36 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 x%5E2-12x%2B36, replace -12x with -6x%2B-6x (notice -6x%2B-6x adds up to -12x. So it is equivalent to -12x)

x%5E2%2Bhighlight%28-6x%2B-6x%29%2B36


Now let's factor x%5E2-6x-6x%2B36 by grouping:


%28x%5E2-6x%29%2B%28-6x%2B36%29 Group like terms


x%28x-6%29-6%28x-6%29 Factor out the GCF of x out of the first group. Factor out the GCF of -6 out of the second group


%28x-6%29%28x-6%29 Since we have a common term of x-6, we can combine like terms

So x%5E2-6x-6x%2B36 factors to %28x-6%29%28x-6%29


So this also means that x%5E2-12x%2B36 factors to %28x-6%29%28x-6%29 (since x%5E2-12x%2B36 is equivalent to x%5E2-6x-6x%2B36)


note: %28x-6%29%28x-6%29 is equivalent to %28x-6%29%5E2 since the term x-6 occurs twice. So x%5E2-12x%2B36 also factors to %28x-6%29%5E2



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



Answer:
So x%5E2-12x%2B36 factors to %28x-6%29%5E2


expressions/119714: Is this the right factoring
x^2-5x-6
(x-2)(x-3)
1 solutions

Answer 87708 by jim_thompson5910(28504) About Me  on 2008-01-11 16:00:04 (Show Source):
You can put this solution on YOUR website!
No it is not. If you foil %28x-2%29%28x-3%29 you'll get x%5E2-5x%2B6




Looking at x%5E2-5x-6 we can see that the first term is x%5E2 and the last term is -6 where the coefficients are 1 and -6 respectively.

Now multiply the first coefficient 1 and the last coefficient -6 to get -6. Now what two numbers multiply to -6 and add to the middle coefficient -5? Let's list all of the factors of -6:



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

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

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

note: remember, the product of a negative and a positive number is a negative number


Now which of these pairs add to -5? Lets make a table of all of the pairs of factors we multiplied and see which two numbers add to -5

First NumberSecond NumberSum
1-61+(-6)=-5
2-32+(-3)=-1
-16-1+6=5
-23-2+3=1



From this list we can see that 1 and -6 add up to -5 and multiply to -6


Now looking at the expression x%5E2-5x-6, replace -5x with 1x%2B-6x (notice 1x%2B-6x adds up to -5x. So it is equivalent to -5x)

x%5E2%2Bhighlight%281x%2B-6x%29%2B-6


Now let's factor x%5E2%2B1x-6x-6 by grouping:


%28x%5E2%2B1x%29%2B%28-6x-6%29 Group like terms


x%28x%2B1%29-6%28x%2B1%29 Factor out the GCF of x out of the first group. Factor out the GCF of -6 out of the second group


%28x-6%29%28x%2B1%29 Since we have a common term of x%2B1, we can combine like terms

So x%5E2%2B1x-6x-6 factors to %28x-6%29%28x%2B1%29


So this also means that x%5E2-5x-6 factors to %28x-6%29%28x%2B1%29 (since x%5E2-5x-6 is equivalent to x%5E2%2B1x-6x-6)



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



Answer:
So x%5E2-5x-6 factors to %28x-6%29%28x%2B1%29


expressions/119713: Was I able to factor this correctly?
4x^2-15x-25
=(2x+5)(2x+5)


1 solutions

Answer 87707 by jim_thompson5910(28504) About Me  on 2008-01-11 15:56:22 (Show Source):
You can put this solution on YOUR website!

Looking at 4x%5E2-15x-25 we can see that the first term is 4x%5E2 and the last term is -25 where the coefficients are 4 and -25 respectively.

Now multiply the first coefficient 4 and the last coefficient -25 to get -100. Now what two numbers multiply to -100 and add to the middle coefficient -15? Let's list all of the factors of -100:



Factors of -100:
1,2,4,5,10,20,25,50

-1,-2,-4,-5,-10,-20,-25,-50 ...List the negative factors as well. This will allow us to find all possible combinations

These factors pair up and multiply to -100
(1)*(-100)
(2)*(-50)
(4)*(-25)
(5)*(-20)
(-1)*(100)
(-2)*(50)
(-4)*(25)
(-5)*(20)

note: remember, the product of a negative and a positive number is a negative number


Now which of these pairs add to -15? Lets make a table of all of the pairs of factors we multiplied and see which two numbers add to -15

First NumberSecond NumberSum
1-1001+(-100)=-99
2-502+(-50)=-48
4-254+(-25)=-21
5-205+(-20)=-15
-1100-1+100=99
-250-2+50=48
-425-4+25=21
-520-5+20=15



From this list we can see that 5 and -20 add up to -15 and multiply to -100


Now looking at the expression 4x%5E2-15x-25, replace -15x with 5x%2B-20x (notice 5x%2B-20x adds up to -15x. So it is equivalent to -15x)

4x%5E2%2Bhighlight%285x%2B-20x%29%2B-25


Now let's factor 4x%5E2%2B5x-20x-25 by grouping:


%284x%5E2%2B5x%29%2B%28-20x-25%29 Group like terms


x%284x%2B5%29-5%284x%2B5%29 Factor out the GCF of x out of the first group. Factor out the GCF of -5 out of the second group


%28x-5%29%284x%2B5%29 Since we have a common term of 4x%2B5, we can combine like terms

So 4x%5E2%2B5x-20x-25 factors to %28x-5%29%284x%2B5%29


So this also means that 4x%5E2-15x-25 factors to %28x-5%29%284x%2B5%29 (since 4x%5E2-15x-25 is equivalent to 4x%5E2%2B5x-20x-25)




So 4x%5E2-15x-25 factors to %28x-5%29%284x%2B5%29







Polynomials-and-rational-expressions/119703: factor completely -3t^3+3t^2-6t
1 solutions

Answer 87705 by jim_thompson5910(28504) About Me  on 2008-01-11 15:30:53 (Show Source):
You can put this solution on YOUR website!

-3t%5E3%2B3t%5E2-6t Start with the given expression


-3t%28t%5E2-t%2B2%29 Factor out the GCF -3t


Now let's focus on the inner expression t%5E2-t%2B2




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



Looking at t%5E2-t%2B2 we can see that the first term is t%5E2 and the last term is 2 where the coefficients are 1 and 2 respectively.

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



Factors of 2:
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 2
1*2
(-1)*(-2)

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


Now which of these pairs add to -1? Lets make a table of all of the pairs of factors we multiplied and see which two numbers add to -1

First NumberSecond NumberSum
121+2=3
-1-2-1+(-2)=-3

None of these pairs of factors add to -1. So the expression t%5E2-t%2B2 cannot be factored

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





Answer:
So -3t%5E3%2B3t%5E2-6t factors to -3t%28t%5E2-t%2B2%29


Equations/119697: Can you help me with this equation?
Calculate the total rent paid on an apartment for n months if the rent is $565 a month
1 solutions

Answer 87689 by jim_thompson5910(28504) About Me  on 2008-01-11 13:56:00 (Show Source):
You can put this solution on YOUR website!
To find the total rent after 2 months, just multiply 2 and 565 to get 2%2A565=1130. To find the total rent after 3 months, just multiply 3 and 565 to get 3%2A565=1695. This pattern continues...

So to find the total rent after n months, just multiply n and 565 to get n%2A565=565n.


So the total rent due after n months is 565n


Linear-equations/119694: graph equation
y=3\4x+2
1 solutions

Answer 87687 by jim_thompson5910(28504) About Me  on 2008-01-11 13:38:53 (Show Source):
You can put this solution on YOUR website!
Solved by pluggable solver: Graphing Linear Equations
In order to graph y=%283%2F4%29%2Ax%2B2 we only need to plug in two points to draw the line

So lets plug in some points

Plug in x=-8

y=%283%2F4%29%2A%28-8%29%2B2

y=-24%2F4%2B2 Multiply

y=-16%2F4 Add

y=-4 Reduce

So here's one point (-8,-4)




Now lets find another point

Plug in x=-4

y=%283%2F4%29%2A%28-4%29%2B2

y=-12%2F4%2B2 Multiply

y=-4%2F4 Add

y=-1 Reduce

So here's another point (-4,-1). Add this to our graph





Now draw a line through these points

So this is the graph of y=%283%2F4%29%2Ax%2B2 through the points (-8,-4) and (-4,-1)


So from the graph we can see that the slope is 3%2F4 (which tells us that in order to go from point to point we have to start at one point and go up 3 units and to the right 4 units to get to the next point) the y-intercept is (0,2)and the x-intercept is (-2.66666666666667,0) ,or (-8%2F3,0)


We could graph this equation another way. Since b=2 this tells us that the y-intercept (the point where the graph intersects with the y-axis) is (0,2).


So we have one point (0,2)





Now since the slope is 3%2F4, this means that in order to go from point to point we can use the slope to do so. So starting at (0,2), we can go up 3 units



and to the right 4 units to get to our next point


Now draw a line through those points to graph y=%283%2F4%29%2Ax%2B2


So this is the graph of y=%283%2F4%29%2Ax%2B2 through the points (0,2) and (4,5)


Linear-equations/119695: graph equation using intercept method

2x+3y=6 2x-3y=12
1 solutions

Answer 87686 by jim_thompson5910(28504) About Me  on 2008-01-11 13:37:29 (Show Source):
You can put this solution on YOUR website!
#1



2%2Ax%2B3%2Ay=6 Start with the given equation

Let's find the x-intercept

To find the x-intercept, let y=0 and solve for x:
2%2Ax%2B3%2A%280%29=6 Plug in y=0

2%2Ax=6 Simplify

x=6%2F2 Divide both sides by 2


x=3 Reduce



So the x-intercept is (note: the x-intercept will always have a y-coordinate equal to zero)



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

2%2Ax%2B3%2Ay=6 Start with the given equation

Now let's find the y-intercept

To find the y-intercept, let x=0 and solve for y:
2%2A%280%29%2B3%2Ay=6 Plug in x=0

3%2Ay=6 Simplify

x=6%2F3 Divide both sides by 3



y=2 Reduce



So the y-intercept is (note: the y-intercept will always have a x-coordinate equal to zero)

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

So we have these intercepts:
x-intercept:

y-intercept:



Now plot the two points and




Now draw a line through the two points to graph 2%2Ax%2B3%2Ay=6
graph of 2%2Ax%2B3%2Ay=6 through the points and








#2



2%2Ax-3%2Ay=12 Start with the given equation

Let's find the x-intercept

To find the x-intercept, let y=0 and solve for x:
2%2Ax-3%2A%280%29=12 Plug in y=0

2%2Ax=12 Simplify

x=12%2F2 Divide both sides by 2


x=6 Reduce



So the x-intercept is (note: the x-intercept will always have a y-coordinate equal to zero)



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

2%2Ax-3%2Ay=12 Start with the given equation

Now let's find the y-intercept

To find the y-intercept, let x=0 and solve for y:
2%2A%280%29-3%2Ay=12 Plug in x=0

3%2Ay=12 Simplify

x=12%2F-3 Divide both sides by -3



y=-4 Reduce



So the y-intercept is (note: the y-intercept will always have a x-coordinate equal to zero)

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

So we have these intercepts:
x-intercept:

y-intercept:



Now plot the two points and




Now draw a line through the two points to graph 2%2Ax-3%2Ay=12
graph of 2%2Ax-3%2Ay=12 through the points and


Quadratic_Equations/119661: What is the value of k if one root of (3k+1)x^2-2kx=-5 is 1?
1 solutions

Answer 87685 by jim_thompson5910(28504) About Me  on 2008-01-11 13:24:35 (Show Source):
You can put this solution on YOUR website!
If 1 is a root, then f%281%29=0.

%283k%2B1%29x%5E2-2kx=-5 Start with the given equation


%283k%2B1%29x%5E2-2kx%2B5=0 Add 5 to both sides


%283k%2B1%29%281%29%5E2-2k%281%29%2B5=0 Plug in x=1


3k%2B1-2k%2B5=0 Simplify


k%2B6=0 Combine like terms on the left side


k=-6Subtract 6 from both sides

--------------------------------------------------------------
Answer:
So our answer is k=-6


Equations/119692: WRITE THE EQUATION IN STANDARD FORM WITH INTEGER COEFFICIENTS
4x-y-7=0
1 solutions

Answer 87684 by jim_thompson5910(28504) About Me  on 2008-01-11 13:18:15 (Show Source):
You can put this solution on YOUR website!
4x-y-7=0 Start with the given equation

4x-y=7 Add 7 to both sides


So the equation is now in standard form Ax%2BBy=C where A=4, B=-1, and C=7


Expressions-with-variables/119691: Solve each system by substitution. check your answer.
y=x-2
y=4x+1
1 solutions

Answer 87683 by jim_thompson5910(28504) About Me  on 2008-01-11 13:15:22 (Show Source):
You can put this solution on YOUR website!

Start with the given system
1y=x-2
y=4x%2B1



4x%2B1=x-2 Plug in y=4x%2B1 into the first equation. In other words, replace each y with 4x%2B1. Notice we've eliminated the y variables. So we now have a simple equation with one unknown.


4x=x-2-1Subtract 1 from both sides


4x-x=-2-1 Subtract x from both sides


3x=-2-1 Combine like terms on the left side


3x=-3 Combine like terms on the right side


x=%28-3%29%2F%283%29 Divide both sides by 3 to isolate x



x=-1 Divide




Now that we know that x=-1, we can plug this into y=4x%2B1 to find y



y=4%28-1%29%2B1 Substitute -1 for each x


y=-3 Simplify


So our answer is x=-1 and y=-3


Human-and-algebraic-language/119644: Ifentify the variables, coefficients,and constants in the algebraic -6x -xy +60
1 solutions

Answer 87682 by jim_thompson5910(28504) About Me  on 2008-01-11 13:13:10 (Show Source):
You can put this solution on YOUR website!

Variables: x and y


Coefficients (ie the numbers in front of the variables): -6 and -1


Constants: 60


Quadratic_Equations/119662: One root of x^2-4x+4a=0 is 2-4i. What is the value of a ?
1 solutions

Answer 87681 by jim_thompson5910(28504) About Me  on 2008-01-11 12:53:13 (Show Source):
You can put this solution on YOUR website!
If 2-4i is a root, then when x=2-4i, the entire left side will equal zero.

x%5E2-4x%2B4a=0 Start with the given equation


%282-4i%29%5E2-4%282-4i%29%2B4a=0 Plug in x=2-4i


4-16i%2B16i%5E2-8%2B16i%2B4a=0 Foil and distribute


4-16i%2B16%28-1%29-8%2B16i%2B4a=0 Replace i%5E2 with -1


4-16i-16-8%2B16i%2B4a=0 Multiply

4a-20=0 Combine like terms




4a=0%2B20Add 20 to both sides


4a=20 Combine like terms on the right side


a=%2820%29%2F%284%29 Divide both sides by 4 to isolate a



a=5 Divide

--------------------------------------------------------------
Answer:
So our answer is a=5



Note: you can check this answer by using the quadratic formula


Rational-functions/119617: Hey, I need help with identities in chapter 6 lesson 6 of my book entitled Rational Expressions and Equations it says as follows: Equations that are true for all acceptable replacements of the variable are identities. Determine which equations areidenties.
problem as follows: xsquared + 6x - 16/ x-2 = x + 8
I also need help with solving rational expressions.
This is algebra 2
Thank you so much
I can realy use the help I need to bring up my grade cause I am realy worried about my G.P.A. because I want to get into a very good college.
Thanks again
1 solutions

Answer 87619 by jim_thompson5910(28504) About Me  on 2008-01-10 20:29:22 (Show Source):
You can put this solution on YOUR website!

%28x%5E2%2B6x-16%29%2F%28x-2%29=x%2B8 Start with the given equation. Note: since x%3C%3E2 since that will make the denominator equal to zero

%28%28x%2B8%29%28x-2%29%29%2F%28x-2%29=x%2B8 Factor x%5E2%2B6x-16 to get %28x%2B8%29%28x-2%29


%28x%2B8%29%28x-2%29%2F%28x-2%29=x%2B8 Combine the fractions


%28x%2B8%29cross%28%28x-2%29%29%2Fcross%28%28x-2%29%29=x%2B8 Cancel like terms


x%2B8=x%2B8 Simplify



x=x%2B8-8Subtract 8 from both sides


x-x=8-8 Subtract x from both sides


0x=8-8 Combine like terms on the left side


0x=0 Combine like terms on the right side


0=0 Simplify

Since this equation is always true for any x value, this means %28x%5E2%2B6x-16%29%2F%28x-2%29=x%2B8 is an identity and x can equal any number except 2.


Complex_Numbers/119571: This question is from textbook Algebra and Trigonometry Structure and Method Book 2
sqrt%28-r%2F5%29sqrt%28-20%2Fr%29
1 solutions

Answer 87605 by jim_thompson5910(28504) About Me  on 2008-01-10 18:32:23 (Show Source):
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sqrt%28-r%2F5%29sqrt%28-20%2Fr%29 Start with the given expression. Note: since r%3C%3E0 and we cannot take the square root of a negative number, we must make the restriction r%3C0


sqrt%28%28-r%2F5%29%28-20%2Fr%29%29 Combine the square roots.



sqrt%28%28-r%2F5%29%28-4%2A5%2Fr%29%29 Factor -20 into -4%2A5


sqrt%28%28-cross%28r%29%2Fcross%285%29%29%28-4%2Across%285%29%2Fcross%28r%29%29%29 Cancel like terms



sqrt%28%28-1%29%28-4%29%29 Simplify



sqrt%284%29 Multiply


2 Take the square root of 4 to get 2


logarithm/119567: can you please explain this to me step by step so i can understand it.
log(3-2x) - log (x+9)=0
i hope you can help me understand this
thank you
julie
1 solutions

Answer 87603 by jim_thompson5910(28504) About Me  on 2008-01-10 18:23:43 (Show Source):
You can put this solution on YOUR website!
log%2810%2C%283-2x%29%29-log%2810%2C%28x%2B9%29%29=0 Start with the given equation. Note: Since you did not specify a base, this means that we're going to use the default base 10.

log%2810%2C%28%283-2x%29%2F%28x%2B9%29%29%29=0 Combine the logs using the identity log%28b%2C%28A%29%29-log%28b%2C%28B%29%29=log%28b%2C%28A%2FB%29%29




10%5E%280%29=%283-2x%29%2F%28x%2B9%29 Rewrite the equation using the property: log%28b%2C%28x%29%29=y ====> b%5Ey=x


1=%283-2x%29%2F%28x%2B9%29 Evaluate 10%5E%280%29 to get 1


x%2B9=3-2x Multiply both sides by x%2B9



x=3-2x-9Subtract 9 from both sides


x%2B2x=3-9 Add 2x to both sides


3x=3-9 Combine like terms on the left side


3x=-6 Combine like terms on the right side


x=%28-6%29%2F%283%29 Divide both sides by 3 to isolate x



x=-2 Divide

--------------------------------------------------------------
Answer:
So our answer is x=-2


Inequalities/119564: how do you solve and graph the absolute value 2x > 6?
1 solutions

Answer 87601 by jim_thompson5910(28504) About Me  on 2008-01-10 18:16:47 (Show Source):
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abs%282x%29%3E6 Start with the given inequality


Break up the absolute value (remember, if you have abs%28x%29%3E+a, then x+%3C+-a or x+%3E+a)

2x+%3C+-6 or 2x+%3E+6 Break up the absolute value inequality using the given rule




Now lets focus on the first inequality 2x+%3C+-6


2x%3C-6 Start with the given inequality


x%3C%28-6%29%2F%282%29 Divide both sides by 2 to isolate x



x%3C-3 Divide


Now lets focus on the second inequality 2x+%3E+6


2x%3E6 Start with the given inequality


x%3E%286%29%2F%282%29 Divide both sides by 2 to isolate x



x%3E3 Divide



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

Answer:

So our answer is

x+%3C+-3 or x+%3E+3


which looks like this in interval notation





if you wanted to graph the solution set, you would get

Graph of the solution set in blue and the excluded values represented by open circles


logarithm/119561: can you please explain this to me in step by step form so hopefully i can understand this.
log x 9/4 =2
please help me
thank you
julie
1 solutions

Answer 87599 by jim_thompson5910(28504) About Me  on 2008-01-10 18:11:14 (Show Source):
You can put this solution on YOUR website!
Does this say: "log base x of 9/4 equals 2"? If it does, then...




log%28x%2C%289%2F4%29%29=2 Start with the given equation.


x%5E%282%29=9%2F4 Rewrite the equation using the property: log%28b%2C%28x%29%29=y ====> b%5Ey=x


x=sqrt%289%2F4%29 Take the square root of both sides. Since you cannot take the log of a negative number, I'm going to exclude the negative answer.


x=sqrt%289%29%2Fsqrt%284%29 Break up the square root



x=%283%29%2Fsqrt%284%29 Simplify sqrt%289%29 to get 3


x=%283%29%2F%282%29 Simplify sqrt%284%29 to get 2



So our answer is x=%283%29%2F%282%29


Triangles/119555: In a quadrilateral JKLM, measure angle J=x,measure angle K=2x, measure angle L=2x+10,and measure angle M=3x-5. Find the measure of the angle.
1 solutions

Answer 87598 by jim_thompson5910(28504) About Me  on 2008-01-10 18:05:23 (Show Source):
You can put this solution on YOUR website!
For any quadrilateral, the sum of the 4 angles is 360 degrees. So in this case, J%2BK%2BL%2BM=360


J%2BK%2BL%2BM=360 Start with the given equation


x%2B2x%2B2x%2B10%2B3x-5=360 Plug in J=x, K=2x, L=2x%2B10,and M=3x-5



8x%2B5=360 Combine like terms on the left side


8x=360-5Subtract 5 from both sides


8x=355 Combine like terms on the right side


x=%28355%29%2F%288%29 Divide both sides by 8 to isolate x



x=355%2F8 Reduce



Since x=355%2F8 (which is x=44.375 in decimal form), our first angle is J=44.375



Since x=44.375, we can plug this into K=2x to get

K=2%2844.375%29=88.75

So our second angle is K=88.75



Since x=44.375, we can plug this into L=2x%2B10 to get

L=2%2844.375%29%2B10=88.75%2B10=98.75

So our third angle is L=98.75


Since x=44.375, we can plug this into M=3x-5 to get

M=3%2844.375%29-5=133.125-5=128.125

So our fourth angle is M=128.125

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


So the measures of the four angles are:


J=44.375, K=88.75, L=98.75, and M=128.125



Check:

J%2BK%2BL%2BM=360 Start with the given equation

44.375%2B88.75%2B98.75%2B128.125=360 Plug in J=44.375, K=88.75, L=98.75, and M=128.125

360=360 Add. Since the two sides of the equation are equal, this verifies our answer.


Polynomials-and-rational-expressions/119550: hi i really dont understand what to do for this equation please help me out. thanks i apreciate it.
(16x) over (25x^2-5) times ( 2x^2-x-1) over(8x)

1 solutions

Answer 87596 by jim_thompson5910(28504) About Me  on 2008-01-10 17:54:17 (Show Source):
You can put this solution on YOUR website!
%28%2816x%29%2F%2825x%5E2-5%29%29%28%282x%5E2-x-1%29%2F%288x%29%29 Start with the given expression

%28%2816%28x%29%29%2F%2825x%5E2-5%29%29%28%282x%5E2-x-1%29%2F%288x%29%29 Factor 16x to get 16%28x%29

%28%2816%28x%29%29%2F%285%285x%5E2-1%29%29%29%28%282x%5E2-x-1%29%2F%288x%29%29 Factor 25x%5E2-5 to get 5%285x%5E2-1%29

%28%2816%28x%29%29%2F%285%285x%5E2-1%29%29%29%28%28%28x-1%29%282x%2B1%29%29%2F%288x%29%29 Factor 2x%5E2-x-1 to get %28x-1%29%282x%2B1%29

Factor 8x to get 8%28x%29


16%28x%29%28x-1%29%282x%2B1%29%2F5%285x%5E2-1%298%28x%29 Combine the fractions


16cross%28x%29%28x-1%29%282x%2B1%29%2F5%285x%5E2-1%298cross%28x%29 Cancel like terms



2%28x-1%29%282x%2B1%29%2F5%285x%5E2-1%29 Divide and simplify



So %28%2816x%29%2F%2825x%5E2-5%29%29%28%282x%5E2-x-1%29%2F%288x%29%29 simplifies to 2%28x-1%29%282x%2B1%29%2F5%285x%5E2-1%29



In other words,


Quadratic_Equations/119529: This question is from textbook
determine whether the equation has 2 solutions, 1 solution, or no solution. SHOW WORK! PUT IN STANDARD FORM!
22)x^2-3x+2=0
24)-3x^2+5x-1=0
26)x^2-2x+4=0
28)3x^2-6x+3=0
30)-5x^2+6x-6=0
1 solutions

Answer 87595 by jim_thompson5910(28504) About Me  on 2008-01-10 17:46:15 (Show Source):
You can put this solution on YOUR website!
I'll do the first two to help you get started


#22

From the quadratic formula
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+

the discriminant consists of all of the terms in the square root. So the discriminant is

D=b%5E2-4ac

the discriminant tells us how many solutions (and what type of solutions) we can expect for any quadratic.


Now let's find the discriminant for y=x%5E2-3x%2B2:

D=-3%5E2-4%2A1%2A2 Plug in a=1, b=-3, c=2

D=9-4%2A1%2A2 Square -3 to get 9

D=9-8 Multiply -4*1*2 to get -8

D=1 Combine 9 and -8 to get 1


Since the discriminant equals 1 (which is greater than zero) , this means there are two real solutions. Remember if the discriminant is greater than zero, then the quadratic will have two real solutions.








#24


From the quadratic formula
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+

the discriminant consists of all of the terms in the square root. So the discriminant is

D=b%5E2-4ac

the discriminant tells us how many solutions (and what type of solutions) we can expect for any quadratic.


Now let's find the discriminant for y=-3x%5E2%2B5x-1:

D=5%5E2-4%2A-3%2A-1 Plug in a=-3, b=5, c=-1

D=25-4%2A-3%2A-1 Square 5 to get 25

D=25-12 Multiply -4*-3*-1 to get -12

D=13 Combine 25 and -12 to get 13


Since the discriminant equals 13 (which is greater than zero) , this means there are two real solutions. Remember if the discriminant is greater than zero, then the quadratic will have two real solutions.


test/119540: This question is from textbook Algebra II
I really really need help and I've been searching over the internet for the best source to hepl me unfortunately my school exam on this is tomorrow. But it would really help to know how to do the problems. My main problem is in Chapter 3 of my book , on Solving Linear Systems Alegraically. I don't understand anything about it, it just confuses me .
such as 3x + 4y equals -4
x + 2y equals 2
and in the book it says to solve the linear system using the substituion method.
I'm having problems on problems like that and on graphing in section 3.3 of my book on Graphing and Solving Systems of Linear inequalities.

on pages 159 and 148 mostly those pages
THanks!
1 solutions

Answer 87594 by jim_thompson5910(28504) About Me  on 2008-01-10 17:35:57 (Show Source):
You can put this solution on YOUR website!
Solved by pluggable solver: Solving a linear system of equations by subsitution


Lets start with the given system of linear equations

3%2Ax%2B4%2Ay=-4
1%2Ax%2B2%2Ay=2

Now in order to solve this system by using substitution, we need to solve (or isolate) one variable. I'm going to choose y.

Solve for y for the first equation

4%2Ay=-4-3%2AxSubtract 3%2Ax from both sides

y=%28-4-3%2Ax%29%2F4 Divide both sides by 4.


Which breaks down and reduces to



y=-1-%283%2F4%29%2Ax Now we've fully isolated y

Since y equals -1-%283%2F4%29%2Ax we can substitute the expression -1-%283%2F4%29%2Ax into y of the 2nd equation. This will eliminate y so we can solve for x.


1%2Ax%2B2%2Ahighlight%28%28-1-%283%2F4%29%2Ax%29%29=2 Replace y with -1-%283%2F4%29%2Ax. Since this eliminates y, we can now solve for x.

1%2Ax%2B2%2A%28-1%29%2B2%28-3%2F4%29x=2 Distribute 2 to -1-%283%2F4%29%2Ax

1%2Ax-2-%286%2F4%29%2Ax=2 Multiply



1%2Ax-2-%283%2F2%29%2Ax=2 Reduce any fractions

1%2Ax-%283%2F2%29%2Ax=2%2B2Add 2 to both sides


1%2Ax-%283%2F2%29%2Ax=4 Combine the terms on the right side



%282%2F2%29%2Ax-%283%2F2%29x=4 Make 1 into a fraction with a denominator of 2

%28-1%2F2%29%2Ax=4 Now combine the terms on the left side.


cross%28%282%2F-1%29%28-1%2F2%29%29x=%284%2F1%29%282%2F-1%29 Multiply both sides by 2%2F-1. This will cancel out -1%2F2 and isolate x

So when we multiply 4%2F1 and 2%2F-1 (and simplify) we get



x=-8 <---------------------------------One answer

Now that we know that x=-8, lets substitute that in for x to solve for y

1%28-8%29%2B2%2Ay=2 Plug in x=-8 into the 2nd equation

-8%2B2%2Ay=2 Multiply

2%2Ay=2%2B8Add 8 to both sides

2%2Ay=10 Combine the terms on the right side

cross%28%281%2F2%29%282%29%29%2Ay=%2810%2F1%29%281%2F2%29 Multiply both sides by 1%2F2. This will cancel out 2 on the left side.

y=10%2F2 Multiply the terms on the right side


y=5 Reduce


So this is the other answer


y=5<---------------------------------Other answer


So our solution is

x=-8 and y=5

which can also look like

(-8,5)

Notice if we graph the equations (if you need help with graphing, check out this solver)

3%2Ax%2B4%2Ay=-4
1%2Ax%2B2%2Ay=2

we get


graph of 3%2Ax%2B4%2Ay=-4 (red) and 1%2Ax%2B2%2Ay=2 (green) (hint: you may have to solve for y to graph these) intersecting at the blue circle.


and we can see that the two equations intersect at (-8,5). This verifies our answer.


-----------------------------------------------------------------------------------------------
Check:

Plug in (-8,5) into the system of equations


Let x=-8 and y=5. Now plug those values into the equation 3%2Ax%2B4%2Ay=-4

3%2A%28-8%29%2B4%2A%285%29=-4 Plug in x=-8 and y=5


-24%2B20=-4 Multiply


-4=-4 Add


-4=-4 Reduce. Since this equation is true the solution works.


So the solution (-8,5) satisfies 3%2Ax%2B4%2Ay=-4



Let x=-8 and y=5. Now plug those values into the equation 1%2Ax%2B2%2Ay=2

1%2A%28-8%29%2B2%2A%285%29=2 Plug in x=-8 and y=5


-8%2B10=2 Multiply


2=2 Add


2=2 Reduce. Since this equation is true the solution works.


So the solution (-8,5) satisfies 1%2Ax%2B2%2Ay=2


Since the solution (-8,5) satisfies the system of equations


3%2Ax%2B4%2Ay=-4
1%2Ax%2B2%2Ay=2


this verifies our answer.




Linear-equations/119522: a line with slope 305and y-intercept (0,4)











9
1 solutions

Answer 87568 by jim_thompson5910(28504) About Me  on 2008-01-10 16:00:01 (Show Source):
You can put this solution on YOUR website!
Is the slope supposed to say "3/5"?




If you want to find the equation of line with a given a slope of 3%2F5 which goes through the point (0,4), 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=%283%2F5%29%28x-0%29 Plug in m=3%2F5, x%5B1%5D=0, and y%5B1%5D=4 (these values are given)


y-4=%283%2F5%29x%2B%283%2F5%29%28-0%29 Distribute 3%2F5

y-4=%283%2F5%29x%2B0 Multiply 3%2F5 and -0 to get 0

y=%283%2F5%29x%2B0%2B4 Add 4 to both sides to isolate y

y=%283%2F5%29x%2B4 Combine like terms 0 and 4 to get 4
------------------------------------------------------------------------------------------------------------
Answer:


So the equation of the line with a slope of 3%2F5 which goes through the point (0,4) is:

y=%283%2F5%29x%2B4 which is now in y=mx%2Bb form where the slope is m=3%2F5 and the y-intercept is b=4

Notice if we graph the equation y=%283%2F5%29x%2B4 and plot the point (0,4), we get (note: if you need help with graphing, check out this solver)

Graph of y=%283%2F5%29x%2B4 through the point (0,4)
and we can see that the point lies on the line. Since we know the equation has a slope of 3%2F5 and goes through the point (0,4), this verifies our answer.


Inequalities/119513: how would you solve this -3 > 7y-3 > -24
1 solutions

Answer 87565 by jim_thompson5910(28504) About Me  on 2008-01-10 15:39:30 (Show Source):
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-3+%3E+7y-3+%3E+-24 Start with the given compound inequality


-24+%3C+7y-3+%3C+-3 Reverse the compound inequality by switching the outer sides and reversing the inequality signs



-21%3C7y%3C0 Add 3 to all sides






-3%3Cy%3C0 Divide every side by 7 to isolate y.



So the solution in interval notation is: (-3,0)


Now let's graph the solution set



Note: at y=-3 there is a open circle (which means this point is excluded) and at y=0 there is a open circle (which means this point is excluded)





expressions/119518: I really need help with these questions.
Evaluate each function for x= -2,0,and 5.
1.) y = 9 + x
2.) y = x^2 - 1

Please help me because I need to get this to my teacher tommorrow.
1 solutions

Answer 87562 by jim_thompson5910(28504) About Me  on 2008-01-10 15:34:29 (Show Source):
You can put this solution on YOUR website!
#1



Let's evaluate f%28-2%29


f%28x%29=9%2B1x Start with the given function.


f%28-2%29=9%2B1%28-2%29 Plug in x=-2. In other words, replace each x with -2.


f%28-2%29=9%2B-2 Multiply 1 and -2 to get -2


f%28-2%29=7 Now combine like terms


-----------Now let's evaluate another value---------


Let's evaluate f%280%29


f%28x%29=9%2B1x Start with the given function.


f%280%29=9%2B1%280%29 Plug in x=0. In other words, replace each x with 0.


f%280%29=9%2B0 Multiply 1 and 0 to get 0


f%280%29=9 Now combine like terms


-----------Now let's evaluate another value---------


Let's evaluate f%285%29


f%28x%29=9%2B1x Start with the given function.


f%285%29=9%2B1%285%29 Plug in x=5. In other words, replace each x with 5.


f%285%29=9%2B5 Multiply 1 and 5 to get 5


f%285%29=14 Now combine like terms








#2




Let's evaluate f%28-2%29


f%28x%29=x%5E2-1 Start with the given function.


f%28-2%29=%28-2%29%5E2-1 Plug in x=-2. In other words, replace each x with -2.


f%28-2%29=%284%29-1 Evaluate %28-2%29%5E2 to get 4.


f%28-2%29=3 Now combine like terms


-----------Now let's evaluate another value---------


Let's evaluate f%280%29


f%28x%29=x%5E2-1 Start with the given function.


f%280%29=%280%29%5E2-1 Plug in x=0. In other words, replace each x with 0.


f%280%29=%280%29-1 Evaluate %280%29%5E2 to get 0.


f%280%29=-1 Now combine like terms


-----------Now let's evaluate another value---------


Let's evaluate f%285%29


f%28x%29=x%5E2-1 Start with the given function.


f%285%29=%285%29%5E2-1 Plug in x=5. In other words, replace each x with 5.


f%285%29=%2825%29-1 Evaluate %285%29%5E2 to get 25.


f%285%29=24 Now combine like terms


Linear-equations/119501: Find the slope and y-intercept.
-4x + 5y = 25
1 solutions

Answer 87549 by jim_thompson5910(28504) About Me  on 2008-01-10 13:17:02 (Show Source):
You can put this solution on YOUR website!
Solved by pluggable solver: Converting Linear Equations in Standard form to Slope-Intercept Form (and vice versa)


-4%2Ax%2B5%2Ay=25Start with the given equation



5%2Ay=25%2B4%2Ax Add 4%2Ax to both sides

y=%281%2F5%29%2825%2B4%2Ax%29 Multiply both sides by 1%2F5

y=%281%2F5%29%2825%29-%281%2F5%29%28-4%29x%29 Distribute 1%2F5

y=25%2F5%2B%284%2F5%29x Multiply

y=%284%2F5%29%2Ax%2B25%2F5 Rearrange the terms

y=%284%2F5%29%2Ax%2B5 Reduce any fractions

So the equation is now in slope-intercept form (y=mx%2Bb) where m=4%2F5 (the slope) and b=5 (the y-intercept)


Radicals/119510: Find the distance between each pair of points.
1. (0,8)and(0,-4)
2. (2,6)and(-3,4)
I'm lost on where to start on this type of problem.
1 solutions

Answer 87548 by jim_thompson5910(28504) About Me  on 2008-01-10 13:15:12 (Show Source):
You can put this solution on YOUR website!
#1


Start with the given distance formula
d=sqrt%28%28x%5B1%5D-x%5B2%5D%29%5E2%2B%28y%5B1%5D-y%5B2%5D%29%5E2%29 where is the first point and is the second point

d=sqrt%28%280-0%29%5E2%2B%288--4%29%5E2%29 Plug in x%5B1%5D=0, x%5B2%5D=0, y%5B1%5D=8, y%5B2%5D=-4

d=sqrt%28%280%29%5E2%2B%2812%29%5E2%29 Evaluate 0-0 to get 0. Evaluate 8--4 to get 12.

d=sqrt%280%2B144%29 Square each value

d=sqrt%28144%29 Add

d=12 Simplify the square root (note: If you need help with simplifying the square root, check out this solver)

So the distance between (0,8) and (0,-4) is 12 units







#2

Start with the given distance formula
d=sqrt%28%28x%5B1%5D-x%5B2%5D%29%5E2%2B%28y%5B1%5D-y%5B2%5D%29%5E2%29 where is the first point and is the second point

d=sqrt%28%282--3%29%5E2%2B%286-4%29%5E2%29 Plug in x%5B1%5D=2, x%5B2%5D=-3, y%5B1%5D=6, y%5B2%5D=4

d=sqrt%28%285%29%5E2%2B%282%29%5E2%29 Evaluate 2--3 to get 5. Evaluate 6-4 to get 2.

d=sqrt%2825%2B4%29 Square each value

d=sqrt%2829%29 Add

So the distance approximates to

d=5.3851648071345

which rounds to
5.39

So the distance between (2,6) and (-3,4) is approximately 5.39 units