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Expressions-with-variables/118753: Rewrite the equation in slope-intercept form. 5x-2y-7=0
1 solutions

Answer 86890 by jim_thompson5910(28504) About Me  on 2008-01-05 16:00:53 (Show Source):
You can put this solution on YOUR website!
5x-2y-7=0 Start with the given equation



-2y-7=0-5xSubtract 5x from both sides


-2y=0-5x%2B7Add 7 to both sides


-2y=-5x%2B7 Combine like terms on the right side


y=%28-5x%2B7%29%2F%28-2%29 Divide both sides by -2 to isolate y



y=%28-5x%29%2F%28-2%29%2B%287%29%2F%28-2%29 Break up the fraction


y=%285%2F2%29x-%287%2F2%29 Reduce


So the equation is in slope-intercept form y=mx%2Bb where m=5%2F2 and b=7%2F2


Exponential-and-logarithmic-functions/118724: 7x³(2x+3)
1 solutions

Answer 86889 by jim_thompson5910(28504) About Me  on 2008-01-05 15:57:11 (Show Source):
You can put this solution on YOUR website!

7x%5E3%282x%2B3%29 Start with the given expression


%287x%5E3%29%282x%29%2B%287x%5E3%29%283%29 Distribute 7x%5E3 among the terms in the parenthesis


14x%5E4%2B%287x%5E3%29%283%29 Multiply 7x%5E3 and 2x to get 14x%5E4

14x%5E4%2B21x%5E3 Multiply 7x%5E3 and 3 to get 21x%5E3


-------------
Answer:
So 7x%5E3%282x%2B3%29 distributes to 14x%5E4%2B21x%5E3

In other words, 7x%5E3%282x%2B3%29=14x%5E4%2B21x%5E3


Exponential-and-logarithmic-functions/118725: xy(x²+3xy+9)
1 solutions

Answer 86888 by jim_thompson5910(28504) About Me  on 2008-01-05 15:56:18 (Show Source):
You can put this solution on YOUR website!

xy%28x%5E2%2B3xy%2B9%29 Start with the given expression


%28xy%29%28x%5E2%29%2B%28xy%29%283xy%29%2B%28xy%29%289%29 Distribute xy among the terms in the parenthesis


x%5E3y%2B%28xy%29%283xy%29%2B%28xy%29%289%29 Multiply xy and x%5E2 to get x%5E3y

x%5E3y%2B3x%5E2y%5E2%2B%28xy%29%289%29 Multiply xy and 3xy to get 3x%5E2y%5E2

x%5E3y%2B3x%5E2y%5E2%2B9xy Multiply xy and 9 to get 9xy


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Answer:
So xy%28x%5E2%2B3xy%2B9%29 distributes to x%5E3y%2B3x%5E2y%5E2%2B9xy

In other words, xy%28x%5E2%2B3xy%2B9%29=x%5E3y%2B3x%5E2y%5E2%2B9xy


Inequalities/118742: This question is from textbook algebra 1
how do you solve the equation -6r-10<3r-8?
1 solutions

Answer 86883 by jim_thompson5910(28504) About Me  on 2008-01-05 15:36:11 (Show Source):
You can put this solution on YOUR website!

-6r-10%3C3r-8 Start with the given inequality



-6r%3C3r-8%2B10Add 10 to both sides


-6r-3r%3C-8%2B10 Subtract 3r from both sides


-9r%3C-8%2B10 Combine like terms on the left side


-9r%3C2 Combine like terms on the right side


r%3E%282%29%2F%28-9%29 Divide both sides by -9 to isolate r (note: Remember, dividing both sides by a negative number flips the inequality sign)



r%3E-2%2F9 Reduce

--------------------------------------------------------------
Answer:
So our answer is r%3E-2%2F9 (which is approximately r%3E-0.222222222222222 in decimal form)


Coordinate-system/118744: What is the graph of x + y = 1 ?
Thank you
1 solutions

Answer 86882 by jim_thompson5910(28504) About Me  on 2008-01-05 15:35:05 (Show Source):
You can put this solution on YOUR website!
Solved by pluggable solver: Graphing Linear Equations


1%2Ax%2B1%2Ay=1Start with the given equation



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

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

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

y=1-%281%29x Multiply

y=-1%2Ax%2B1 Rearrange the terms

y=-1%2Ax%2B1 Reduce any fractions

So the equation is now in slope-intercept form (y=mx%2Bb) where m=-1 (the slope) and b=1 (the y-intercept)

So to graph this equation lets plug in some points

Plug in x=-8

y=-1%2A%28-8%29%2B1

y=8%2B1 Multiply

y=9 Add

So here's one point (-8,9)





Now lets find another point

Plug in x=-7

y=-1%2A%28-7%29%2B1

y=7%2B1 Multiply

y=8 Add

So here's another point (-7,8). Add this to our graph





Now draw a line through these points

So this is the graph of y=-1%2Ax%2B1 through the points (-8,9) and (-7,8)


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


We could graph this equation another way. Since b=1 this tells us that the y-intercept (the point where the graph intersects with the y-axis) is (0,1).


So we have one point (0,1)






Now since the slope is -1%2F1, this means that in order to go from point to point we can use the slope to do so. So starting at (0,1), we can go down 1 units


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



Now draw a line through those points to graph y=-1%2Ax%2B1


So this is the graph of y=-1%2Ax%2B1 through the points (0,1) and (1,0)


Quadratic_Equations/118752: Please help with this problem 3x^2 + x -4 = 0 What is the solution set ?
Thank you
1 solutions

Answer 86881 by jim_thompson5910(28504) About Me  on 2008-01-05 15:33:34 (Show Source):
You can put this solution on YOUR website!
Let's use the quadratic formula to solve for x:


Starting with the general quadratic

ax%5E2%2Bbx%2Bc=0

the general solution using the quadratic equation is:

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



So lets solve 3%2Ax%5E2%2Bx-4=0 ( notice a=3, b=1, and c=-4)




x+=+%28-1+%2B-+sqrt%28+%281%29%5E2-4%2A3%2A-4+%29%29%2F%282%2A3%29 Plug in a=3, b=1, and c=-4



x+=+%28-1+%2B-+sqrt%28+1-4%2A3%2A-4+%29%29%2F%282%2A3%29 Square 1 to get 1



x+=+%28-1+%2B-+sqrt%28+1%2B48+%29%29%2F%282%2A3%29 Multiply -4%2A-4%2A3 to get 48



x+=+%28-1+%2B-+sqrt%28+49+%29%29%2F%282%2A3%29 Combine like terms in the radicand (everything under the square root)



x+=+%28-1+%2B-+7%29%2F%282%2A3%29 Simplify the square root (note: If you need help with simplifying the square root, check out this solver)



x+=+%28-1+%2B-+7%29%2F6 Multiply 2 and 3 to get 6

So now the expression breaks down into two parts

x+=+%28-1+%2B+7%29%2F6 or x+=+%28-1+-+7%29%2F6

Lets look at the first part:

x=%28-1+%2B+7%29%2F6

x=6%2F6 Add the terms in the numerator
x=1 Divide

So one answer is
x=1



Now lets look at the second part:

x=%28-1+-+7%29%2F6

x=-8%2F6 Subtract the terms in the numerator
x=-4%2F3 Divide

So another answer is
x=-4%2F3

So our solutions are:
x=1 or x=-4%2F3

Notice when we graph 3%2Ax%5E2%2Bx-4, we get:

+graph%28+500%2C+500%2C+-14%2C+11%2C+-14%2C+11%2C3%2Ax%5E2%2B1%2Ax%2B-4%29+

and we can see that the roots are x=1 and x=-4%2F3. This verifies our answer


expressions/118750: Please solve2/x - 1/5 =
Thank you
1 solutions

Answer 86880 by jim_thompson5910(28504) About Me  on 2008-01-05 15:32:11 (Show Source):
You can put this solution on YOUR website!
Since there isn't a right side, we cannot solve. However, we can simplify.



%282%29%2F%28x%29-%281%29%2F%285%29 Start with the given expression




Since the denominators are not equal, we need to get them to a common denominator. Since the LCD is 5x, we need to get each denominator to 5x




%28%28%285%29%29%2F%28%285%29%29%29%28%282%29%2F%28x%29%29%2B%281%29%2F%285%29 Multiply %282%29%2F%28x%29 by %28%285%29%29%2F%28%285%29%29



%285%29%282%29%2F%285x%29%2B%281%29%2F%285%29 Combine the fractions



%2810%29%2F%285x%29%2B%281%29%2F%285%29 Multiply 5 and 2 to get 10



%2810%29%2F%285x%29%2B%28%28%28x%29%29%2F%28%28x%29%29%29%28%281%29%2F%285%29%29 Multiply %281%29%2F%285%29 by %28%28x%29%29%2F%28%28x%29%29



%2810%29%2F%285x%29%2B%28x%29%281%29%2F%285x%29 Combine the fractions



%2810%29%2F%285x%29%2B%28x%29%2F%285x%29 Multiply x and 1 to get x




%2810%2Bx%29%2F%285x%29 Since the 2 fractions have the common denominator %285x%29, we can combine them. In order to do that, just combine the numerators.


expressions/118748: Please help with this question - 4x - 15 < 25 is eqivalent to ?
thank you
1 solutions

Answer 86879 by jim_thompson5910(28504) About Me  on 2008-01-05 15:25:57 (Show Source):
You can put this solution on YOUR website!

Do you want to solve for x?

-4x-15%3C25 Start with the given inequality



-4x%3C25%2B15Add 15 to both sides


-4x%3C40 Combine like terms on the right side


x%3E%2840%29%2F%28-4%29 Divide both sides by -4 to isolate x (note: Remember, dividing both sides by a negative number flips the inequality sign)



x%3E-10 Divide

--------------------------------------------------------------
Answer:
So our answer is x%3E-10




Equations/118751: Please help with this question If x + 2/ x - 3 = 0 then x is = to
Thank you
1 solutions

Answer 86878 by jim_thompson5910(28504) About Me  on 2008-01-05 15:24:49 (Show Source):
You can put this solution on YOUR website!
%28x+%2B+2%29%2F%28x+-+3%29+=+0 Start with the given equation


cross%28%28x+-+3%29%29%28%28x+%2B+2%29%2Fcross%28%28x+-+3%29%29%29+=+%28x-3%290 Multiply both sides by x-3


x+%2B+2+=+0 Multiply


x=0-2Subtract 2 from both sides


x=-2 Combine like terms on the right side

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


Expressions-with-variables/118749: write the equation of the line which contains (-3,1) and whose y intercept is -8
1 solutions

Answer 86877 by jim_thompson5910(28504) About Me  on 2008-01-05 15:22:23 (Show Source):
You can put this solution on YOUR website!
If the y-intercept is -8, then the line goes through the point (0,-8)


First lets find the slope through the points (-3,1) and (0,-8)

m=%28y%5B2%5D-y%5B1%5D%29%2F%28x%5B2%5D-x%5B1%5D%29 Start with the slope formula (note: is the first point (-3,1) and is the second point (0,-8))

m=%28-8-1%29%2F%280--3%29 Plug in y%5B2%5D=-8,y%5B1%5D=1,x%5B2%5D=0,x%5B1%5D=-3 (these are the coordinates of given points)

m=+-9%2F3 Subtract the terms in the numerator -8-1 to get -9. Subtract the terms in the denominator 0--3 to get 3


m=-3 Reduce

So the slope is
m=-3

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


Now let's use the point-slope formula to find the equation of the line:



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

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

y-1=%28-3%29%28x--3%29 Plug in m=-3, x%5B1%5D=-3, and y%5B1%5D=1 (these values are given)


y-1=%28-3%29%28x%2B3%29 Rewrite x--3 as x%2B3


y-1=-3x%2B%28-3%29%283%29 Distribute -3

y-1=-3x-9 Multiply -3 and 3 to get -9

y=-3x-9%2B1 Add 1 to both sides to isolate y

y=-3x-8 Combine like terms -9 and 1 to get -8
------------------------------------------------------------------------------------------------------------
Answer:


So the equation of the line which goes through the points (-3,1) and (0,-8) is:y=-3x-8

The equation is now in y=mx%2Bb form (which is slope-intercept form) where the slope is m=-3 and the y-intercept is b=-8

Notice if we graph the equation y=-3x-8 and plot the points (-3,1) and (0,-8), we get this: (note: if you need help with graphing, check out this solver)

Graph of y=-3x-8 through the points (-3,1) and (0,-8)

Notice how the two points lie on the line. This graphically verifies our answer.


Exponential-and-logarithmic-functions/118745: find each product.
3x²(2y+5x)
1 solutions

Answer 86876 by jim_thompson5910(28504) About Me  on 2008-01-05 15:20:47 (Show Source):
You can put this solution on YOUR website!

3x%5E2%282y%2B5x%29 Start with the given expression


%283x%5E2%29%282y%29%2B%283x%5E2%29%285x%29 Distribute 3x%5E2 among the terms in the parenthesis


6x%5E2y%2B%283x%5E2%29%285x%29 Multiply 3x%5E2 and 2y to get 6x%5E2y

6x%5E2y%2B15x%5E3 Multiply 3x%5E2 and 5x to get 15x%5E3


-------------
Answer:
So 3x%5E2%282y%2B5x%29 distributes to 6x%5E2y%2B15x%5E3

In other words, 3x%5E2%282y%2B5x%29=6x%5E2y%2B15x%5E3


expressions/118747: If x - 3(x-2)= 4(x + 1)-8,then x =
Please help
1 solutions

Answer 86874 by jim_thompson5910(28504) About Me  on 2008-01-05 15:10:49 (Show Source):
You can put this solution on YOUR website!

x-3%28x-2%29=4%28x%2B1%29-8 Start with the given equation



x-3x%2B6=4x%2B4-8 Distribute


-2x%2B6=4x%2B4-8 Combine like terms on the left side


-2x%2B6=4x-4 Combine like terms on the right side


-2x=4x-4-6Subtract 6 from both sides


-2x-4x=-4-6 Subtract 4x from both sides


-6x=-4-6 Combine like terms on the left side


-6x=-10 Combine like terms on the right side


x=%28-10%29%2F%28-6%29 Divide both sides by -6 to isolate x



x=5%2F3 Reduce

--------------------------------------------------------------
Answer:
So our answer is x=5%2F3 (which is approximately x=1.66666666666667 in decimal form)


Inequalities/118741: This question is from textbook algebra 1
after you subtract 4 and are left with -d/3 < 6 how do you finish the problem?
1 solutions

Answer 86871 by jim_thompson5910(28504) About Me  on 2008-01-05 14:23:19 (Show Source):
You can put this solution on YOUR website!

-d%2F3%3C6 Start with the given inequality



%283%29%28-d%2F3%29=%283%29%286%29 Multiply both sides by 3


-d=18 Multiply



d%3E%2818%29%2F%28-1%29 Divide both sides by -1 to isolate d (note: Remember, dividing both sides by a negative number flips the inequality sign)



d%3E-18 Divide

--------------------------------------------------------------
Answer:
So our answer is d%3E-18





Linear-equations/118701: My brain is on shut down from all my equations and this problem has me lost. Help Please!! Angela
Solve the following system of linear inequalities by graphing.
x – y <= 3 x + 2y ,=6


1 solutions

Answer 86870 by jim_thompson5910(28504) About Me  on 2008-01-05 14:09:29 (Show Source):
You can put this solution on YOUR website!

Start with the given system of inequalities
x-y%3C=3
x%2B2y%3C=6

In order to graph this system of inequalities, we need to graph each inequality one at a time.


First lets graph the first inequality x-y%3C=3
In order to graph x-y%3C=3, we need to graph the equation x-y=3 (just replace the inequality sign with an equal sign).
So lets graph the line x-y=3 (note: if you need help with graphing, check out this solver)
+graph%28+500%2C+500%2C+-20%2C+20%2C+-20%2C+20%2C+x-3%29+ graph of x-y=3
Now lets pick a test point, say (0,0). Any point will work, (just make sure the point doesn't lie on the line) but this point is the easiest to work with. Now evaluate the inequality x-y%3C=3 with the test point

Substitute (0,0) into the inequality
%280%29-%280%29%3C=3 Plug in x=0 and y=0
0%3C=3 Simplify



(note: for some reason, some of the following images do not display correctly in Internet Explorer. So I recommend the use of
Firefox to see these images.)


Since this inequality is true, we simply shade the entire region that contains (0,0)
Graph of x-y%3C=3 with the boundary (which is the line x-y=3 in red) and the shaded region (in green)

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


Now lets graph the second inequality x%2B2y%3C=6
In order to graph x%2B2y%3C=6, we need to graph the equation x%2B2y=6 (just replace the inequality sign with an equal sign).
So lets graph the line x%2B2y=6 (note: if you need help with graphing, check out this solver)
+graph%28+500%2C+500%2C+-20%2C+20%2C+-20%2C+20%2C+-%281%2F2%29x%2B3%29+ graph of x%2B2y=6
Now lets pick a test point, say (0,0). Any point will work, (just make sure the point doesn't lie on the line) but this point is the easiest to work with. Now evaluate the inequality x%2B2y%3C=6 with the test point

Substitute (0,0) into the inequality
%280%29%2B2%280%29%3C=6 Plug in x=0 and y=0
0%3C=6 Simplify



Since this inequality is true, we simply shade the entire region that contains (0,0)
Graph of x%2B2y%3C=6 with the boundary (which is the line x%2B2y=6 in red) and the shaded region (in green)

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


So we essentially have these 2 regions:

Region #1
Graph of x-y%3C=3


Region #2
Graph of x%2B2y%3C=6




When these inequalities are graphed on the same coordinate system, the regions overlap to produce this region. It's a little hard to see, but after evenly shading each region, the intersecting region will be the most shaded in.







Here is a cleaner look at the intersection of regions




Here is the intersection of the 2 regions represented by the series of dots


Exponential-and-logarithmic-functions/118710: find each product
2xy(3x²-xy+7)
1 solutions

Answer 86869 by jim_thompson5910(28504) About Me  on 2008-01-05 14:07:03 (Show Source):
You can put this solution on YOUR website!
2xy%283x%5E2-xy%2B7%29 Start with the given expression


2xy%283x%5E2%29-2xy%28xy%29%2B2xy%287%29 Distribute


6x%5E3y-2x%5E2y%5E2%2B14xy Multiply


Quadratic_Equations/118736: Please help to solve this problem. 3x^2 + x - 0 =
Thanking you
1 solutions

Answer 86868 by jim_thompson5910(28504) About Me  on 2008-01-05 14:01:36 (Show Source):
You can put this solution on YOUR website!

3x%5E2%2Bx-0=0 Start with the given equation


3x%5E2%2Bx=0 Remove the zero term on the left



x%283x%2B1%29=0 Factor the left side


Now set each factor equal to zero:
x=0 or 3x%2B1=0

x=0 or x=-1%2F3 Now solve for x in each case


So our answer is
x=0 or x=-1%2F3


Notice if we graph y=3x%5E2%2Bx-0 we can see that the roots are x=0 and x=-1%2F3 . So this visually verifies our answer.


+graph%28500%2C500%2C-3%2C3%2C-3%2C3%2C0%2C+3x%5E2%2Bx%29+


Linear-equations/118738: In a standard xy-coordinate system,the graph of the equation y = -3x + 8 is
Thanking you
1 solutions

Answer 86867 by jim_thompson5910(28504) About Me  on 2008-01-05 13:59:37 (Show Source):
You can put this solution on YOUR website!
Solved by pluggable solver: Graphing Linear Equations
In order to graph y=-3%2Ax%2B8 we only need to plug in two points to draw the line

So lets plug in some points

Plug in x=0

y=-3%2A%280%29%2B8

y=0%2B8 Multiply

y=8 Add

So here's one point (0,8)




Now lets find another point

Plug in x=1

y=-3%2A%281%29%2B8

y=-3%2B8 Multiply

y=5 Add

So here's another point (1,5). Add this to our graph





Now draw a line through these points

So this is the graph of y=-3%2Ax%2B8 through the points (0,8) and (1,5)


So from the graph we can see that the slope is -3%2F1 (which tells us that in order to go from point to point we have to start at one point and go down -3 units and to the right 1 units to get to the next point), the y-intercept is (0,8)and the x-intercept is (2.66666666666667,0) ,or (8%2F3,0)


We could graph this equation another way. Since b=8 this tells us that the y-intercept (the point where the graph intersects with the y-axis) is (0,8).


So we have one point (0,8)





Now since the slope is -3%2F1, this means that in order to go from point to point we can use the slope to do so. So starting at (0,8), we can go down 3 units



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


Now draw a line through those points to graph y=-3%2Ax%2B8


So this is the graph of y=-3%2Ax%2B8 through the points (0,8) and (1,5)


Expressions-with-variables/118739: what are the x and y- intercept of the line -12x+6y=12
1 solutions

Answer 86866 by jim_thompson5910(28504) About Me  on 2008-01-05 13:58:21 (Show Source):
You can put this solution on YOUR website!

-12%2Ax%2B6%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:
-12%2Ax%2B6%2A%280%29=12 Plug in y=0

-12%2Ax=12 Simplify

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


x=-1 Reduce



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



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

-12%2Ax%2B6%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:
-12%2A%280%29%2B6%2Ay=12 Plug in x=0

-6%2Ay=12 Simplify

x=12%2F6 Divide both sides by 6



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:



Exponential-and-logarithmic-functions/118727: find each product
(x-y)(x²-xy+y²)
1 solutions

Answer 86865 by jim_thompson5910(28504) About Me  on 2008-01-05 13:37:27 (Show Source):
You can put this solution on YOUR website!

%28x-y%29%28x%5E2-xy%2By%5E2%29 Start with the given expression



x%28x%5E2-xy%2By%5E2%29-y%28x%5E2-xy%2By%5E2%29 Expand the expression. Remember for something like %28a%2Bb%29%28c%2Bd%2Be%29 it expands to a%28c%2Bd%2Be%29%2Bb%28c%2Bd%2Be%29


Distribute


x%5E3-x%5E2y%2Bxy%5E2-yx%5E2%2By%5E2x-y%5E3 Multiply


-y%5E3%2B2xy%5E2-2x%5E2y%2Bx%5E3 Combine like terms



x%5E3-2x%5E2y%2B2xy%5E2-y%5E3 Rearrange the terms



So %28x-y%29%28x%5E2-xy%2By%5E2%29 expands and simplifies to x%5E3-2x%5E2y%2B2xy%5E2-y%5E3.

In other words, %28x-y%29%28x%5E2-xy%2By%5E2%29=x%5E3-2x%5E2y%2B2xy%5E2-y%5E3


Exponential-and-logarithmic-functions/118729: Find each product.

(x³+x²+1)(x²-x-5)
1 solutions

Answer 86864 by jim_thompson5910(28504) About Me  on 2008-01-05 13:33:34 (Show Source):
You can put this solution on YOUR website!

%28x%5E3%2Bx%5E2%2B1%29%28x%5E2-x-5%29 Start with the given expression



x%5E3%28x%5E2-x-5%29%2Bx%5E2%28x%5E2-x-5%29%2B1%28x%5E2-x-5%29 Expand the expression. Remember for something like %28a%2Bb%2Bc%29%28d%2Be%2Bf%29 it expands to a%28d%2Be%2Bf%29%2Bb%28d%2Be%2Bf%29%2Bc%28d%2Be%2Bf%29


Distribute


x%5E5-x%5E4-5x%5E3%2Bx%5E4-x%5E3-5x%5E2%2Bx%5E2-x-5 Multiply


-4x%5E2-6x%5E3-x%2Bx%5E5-5 Combine like terms



x%5E5-6x%5E3-4x%5E2-x-5 Now rearrange the terms in descending order


So %28x%5E3%2Bx%5E2%2B1%29%28x%5E2-x-5%29 expands and simplifies to x%5E5-6x%5E3-4x%5E2-x-5.

In other words, %28x%5E3%2Bx%5E2%2B1%29%28x%5E2-x-5%29=x%5E5-6x%5E3-4x%5E2-x-5




If you need more help with multiplying polynomials, check out this Long Multiplication Calculator


Exponential-and-logarithmic-functions/118711: Find each product
(3x-2)(2x²+3x-1)
1 solutions

Answer 86863 by jim_thompson5910(28504) About Me  on 2008-01-05 13:31:51 (Show Source):
You can put this solution on YOUR website!

%283x-2%29%282x%5E2%2B3x-1%29 Start with the given expression



3x%282x%5E2%2B3x-1%29-2%282x%5E2%2B3x-1%29 Expand the expression. Remember for something like %28a%2Bb%29%28c%2Bd%2Be%29 it expands to a%28c%2Bd%2Be%29%2Bb%28c%2Bd%2Be%29


Distribute


6x%5E3%2B9x%5E2-3x-4x%5E2-6x%2B2 Multiply


5x%5E2%2B6x%5E3-9x%2B2 Combine like terms



6x%5E3%2B5x%5E2-9x%2B2 Now rearrange the terms in descending order


So %283x-2%29%282x%5E2%2B3x-1%29 expands and simplifies to 6x%5E3%2B5x%5E2-9x%2B2.

In other words, %283x-2%29%282x%5E2%2B3x-1%29=6x%5E3%2B5x%5E2-9x%2B2




If you need more help with multiplying polynomials, check out this Long Multiplication Calculator


absolute-value/118682: what are the solutions to the absolute value equation /x+7/+5=17 ?
/=absolute value bars
choices:
A 5 and -19
B 5 and -5
C 19 and -5
D 12 adn -5
1 solutions

Answer 86810 by jim_thompson5910(28504) About Me  on 2008-01-04 19:11:04 (Show Source):
You can put this solution on YOUR website!

abs%28x%2B7%29%2B5=17 Start with the given equation


abs%28x%2B7%29=12 Subtract 5 from both sides.


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

x%2B7=-12 or x%2B7=12 Set the expression x%2B7 equal to the original value 12 and it's opposite -12




Now lets focus on the first equation x%2B7=-12


x=-12-7Subtract 7 from both sides


x=-19 Combine like terms on the right side

So our first solution is x=-19





Now lets focus on the second equation x%2B7=12


x=12-7Subtract 7 from both sides


x=5 Combine like terms on the right side


So our second solution is x=5



So this means the answer is x=-19 or x=5 which means the answer is A)


Expressions-with-variables/118677: How do you write an equation for the line (in slope-intercept form) with the given information:
1.is vertical and passes through (4, 11)
2.passs thrugh (7, -10) and (4, -16)
3.passes through (2, 18) and (4, 17)

(P.s. they are seperate problems 123)
1 solutions

Answer 86806 by jim_thompson5910(28504) About Me  on 2008-01-04 17:04:47 (Show Source):
You can put this solution on YOUR website!
#1
All vertical lines are of the form x=k where k is the x-coordinate of the points that the line goes through. So in this case, the equation of the line that passes through (4, 11) is x=4

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

#2

First lets find the slope through the points (7,-10) and (4,-16)

m=%28y%5B2%5D-y%5B1%5D%29%2F%28x%5B2%5D-x%5B1%5D%29 Start with the slope formula (note: is the first point (7,-10) and is the second point (4,-16))

m=%28-16--10%29%2F%284-7%29 Plug in y%5B2%5D=-16,y%5B1%5D=-10,x%5B2%5D=4,x%5B1%5D=7 (these are the coordinates of given points)

m=+-6%2F-3 Subtract the terms in the numerator -16--10 to get -6. Subtract the terms in the denominator 4-7 to get -3


m=2 Reduce

So the slope is
m=2

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


Now let's use the point-slope formula to find the equation of the line:



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

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

y--10=%282%29%28x-7%29 Plug in m=2, x%5B1%5D=7, and y%5B1%5D=-10 (these values are given)


y%2B10=%282%29%28x-7%29 Rewrite y--10 as y%2B10


y%2B10=2x%2B%282%29%28-7%29 Distribute 2

y%2B10=2x-14 Multiply 2 and -7 to get -14

y=2x-14-10 Subtract 10 from both sides to isolate y

y=2x-24 Combine like terms -14 and -10 to get -24
------------------------------------------------------------------------------------------------------------
Answer:


So the equation of the line which goes through the points (7,-10) and (4,-16) is:y=2x-24

The equation is now in y=mx%2Bb form (which is slope-intercept form) where the slope is m=2 and the y-intercept is b=-24

Notice if we graph the equation y=2x-24 and plot the points (7,-10) and (4,-16), we get this: (note: if you need help with graphing, check out this solver)

Graph of y=2x-24 through the points (7,-10) and (4,-16)

Notice how the two points lie on the line. This graphically verifies our answer.


----------
#3

First lets find the slope through the points (2,18) and (4,17)

m=%28y%5B2%5D-y%5B1%5D%29%2F%28x%5B2%5D-x%5B1%5D%29 Start with the slope formula (note: is the first point (2,18) and is the second point (4,17))

m=%2817-18%29%2F%284-2%29 Plug in y%5B2%5D=17,y%5B1%5D=18,x%5B2%5D=4,x%5B1%5D=2 (these are the coordinates of given points)

m=+-1%2F2 Subtract the terms in the numerator 17-18 to get -1. Subtract the terms in the denominator 4-2 to get 2

So the slope is
m=-1%2F2

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


Now let's use the point-slope formula to find the equation of the line:



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

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

y-18=%28-1%2F2%29%28x-2%29 Plug in m=-1%2F2, x%5B1%5D=2, and y%5B1%5D=18 (these values are given)


y-18=%28-1%2F2%29x%2B%28-1%2F2%29%28-2%29 Distribute -1%2F2

y-18=%28-1%2F2%29x%2B1 Multiply -1%2F2 and -2 to get 2%2F2. Now reduce 2%2F2 to get 1

y=%28-1%2F2%29x%2B1%2B18 Add 18 to both sides to isolate y

y=%28-1%2F2%29x%2B19 Combine like terms 1 and 18 to get 19
------------------------------------------------------------------------------------------------------------
Answer:


So the equation of the line which goes through the points (2,18) and (4,17) is:y=%28-1%2F2%29x%2B19

The equation is now in y=mx%2Bb form (which is slope-intercept form) where the slope is m=-1%2F2 and the y-intercept is b=19

Notice if we graph the equation y=%28-1%2F2%29x%2B19 and plot the points (2,18) and (4,17), we get this: (note: if you need help with graphing, check out this
solver)

Graph of y=%28-1%2F2%29x%2B19 through the points (2,18) and (4,17)

Notice how the two points lie on the line. This graphically verifies our answer.


Linear_Equations_And_Systems_Word_Problems/118671: Write an equation that is parrallel and perpendicular to the given line.
y=-1/3x+2
1 solutions

Answer 86800 by jim_thompson5910(28504) About Me  on 2008-01-04 14:46:54 (Show Source):
You can put this solution on YOUR website!
An equation that is parallel has the same slope. So the slope of this parallel line is m=-1%2F3. Now just replace the 2 with any number such as 5 to get: y=%28-1%2F3%29x%2B5

So one parallel line is y=%28-1%2F3%29x%2B5


Notice if we graph the two equations, we can see that they are parallel. So this verifies our answer.


+graph%28+500%2C+500%2C+-10%2C+10%2C+-10%2C+10%2C+%28-1%2F3%29x%2B2%2C%28-1%2F3%29x%2B5%29+ Graph of y=%28-1%2F3%29x%2B2 (red) and y=%28-1%2F3%29x%2B5 (green)



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

An equation that is perpendicular has an negated inverted slope. Since the original slope is m=-1%2F3, the perpendicular slope is -1%2Fm=-1%2F%28-1%2F3%29=%28-1%2F1%29%2A%28-3%2F1%29=3%2F1=3

So the perpendicular slope is m=3

y=3x%2B2 Now just replace the slope of m=-1%2F3 with the new slope m=3 to get a perpendicular line.


So one perpendicular line is y=3x%2B2



Notice if we graph the two equations, we can see that they are perpendicular. So this verifies our answer.


+graph%28+500%2C+500%2C+-10%2C+10%2C+-10%2C+10%2C+%28-1%2F3%29x%2B2%2C3x%2B2%29+ Graph of y=%28-1%2F3%29x%2B2 (red) and y=3x%2B2 (green)


Angles/118669: Hello,
I am a freshman student having problems in goemetry. It would be wonderful if I could have a little extra help on a few problems. I would greatly appreciate it. :) Here is my first problem.
A calculation shows that an angle has a measure of 113.05 degrees.
This angle can be written in the form A B', measured in degrees and minutes.
What is the sum of A and B?

Note: In the second sentence the A has a degree symbol after it.

This is how far I got into the problem. 113 + ?/60 + ?/ 3600






1 solutions

Answer 86798 by jim_thompson5910(28504) About Me  on 2008-01-04 14:29:18 (Show Source):
You can put this solution on YOUR website!
Since the angle is 113.05 degrees, this means A=113 (just take the whole part of the number). Now take the decimal portion 0.05 and multiply it by 60 (since there are 60 minutes in a degree) to get 0.05%2A60=3. So this means that 0.05 degrees is 3 minutes which means B=3


So the sum of A and B is: A%2BB=113%2B3=116


Numeric_Fractions/118668: If you have a negative improper fraction like -29/16 If you simplify that is it still a negative?
1 solutions

Answer 86797 by jim_thompson5910(28504) About Me  on 2008-01-04 14:22:57 (Show Source):
You can put this solution on YOUR website!

Well you can't reduce the fraction, but you can convert it to a mixed fraction.



-29%2F16 Start with the given improper fraction

%28-16-13%29%2F16 Break up -29 into -16-13. Notice how -16 is a multiple of 16.


-16%2F16-13%2F16 Break up the fraction.


-1-13%2F16 Reduce -16%2F16 to get -1.

-1%2613%2F16 Simplify. Remember -1-13%2F16 is the same as -1%2613%2F16.


So the improper fraction -29%2F16 is the mixed fraction -1%2613%2F16.


So the fraction is still negative


Rectangles/118667: What is the area of a rectangle with a length of 45 and diagonals of 51?
1 solutions

Answer 86795 by jim_thompson5910(28504) About Me  on 2008-01-04 13:13:33 (Show Source):
You can put this solution on YOUR website!
If we cut the rectangle in half along the diagonal, we get this triangle




Since we can see that the triangle has legs of x and 45 with a hypotenuse of 51, we can use Pythagoreans theorem to find the unknown side.


Pythagoreans theorem:

a%5E2%2Bb%5E2=c%5E2 where a and b are the legs of the triangle and c is the hypotenuse



x%5E2%2B45%5E2=51%5E2 Plug in a=x, b=45, and c=51. Now lets solve for x


+x++%5E+2+%2B+2+0+2+5+=+2+6+0+1 Square each individual term



+x++%5E+2+=+2+6+0+1+-+2+0+2+5 Subtract 2025 from both sides


+x++%5E+2+=+5+7+6 Combine like terms


s+q+r+t+%28++x++%5E+2+%29+=+s+q+r+t+%28+5+7+6+%29 Take the square root of both sides



x=24 Simplify the square root




So the width is 24


A=24%2A45=1080 Now multiply 24 and 45 to get the area


So the area of the rectangle is 1080




Polynomials-and-rational-expressions/118666: x^2+3x+1
_________
x-3
1 solutions

Answer 86794 by jim_thompson5910(28504) About Me  on 2008-01-04 13:08:02 (Show Source):
You can put this solution on YOUR website!

Let's simplify this expression using synthetic division


Start with the given expression %28x%5E2+%2B+3x+%2B+1%29%2F%28x-3%29

First lets find our test zero:

x-3=0 Set the denominator x-3 equal to zero

x=3 Solve for x.

so our test zero is 3


Now set up the synthetic division table by placing the test zero in the upper left corner and placing the coefficients of the numerator to the right of the test zero.
3|131
|

Start by bringing down the leading coefficient (it is the coefficient with the highest exponent which is 1)
3|131
|
1

Multiply 3 by 1 and place the product (which is 3) right underneath the second coefficient (which is 3)
3|131
|3
1

Add 3 and 3 to get 6. Place the sum right underneath 3.
3|131
|3
16

Multiply 3 by 6 and place the product (which is 18) right underneath the third coefficient (which is 1)
3|131
|318
16

Add 18 and 1 to get 19. Place the sum right underneath 18.
3|131
|318
1619

Since the last column adds to 19, we have a remainder of 19. This means x-3 is not a factor of x%5E2+%2B+3x+%2B+1
Now lets look at the bottom row of coefficients:

The first 2 coefficients (1,6) form the quotient

x+%2B+6

and the last coefficient 19, is the remainder, which is placed over x-3 like this

19%2F%28x-3%29



Putting this altogether, we get:

x+%2B+6%2B19%2F%28x-3%29

So %28x%5E2+%2B+3x+%2B+1%29%2F%28x-3%29=x+%2B+6%2B19%2F%28x-3%29

which looks like this in remainder form:
%28x%5E2+%2B+3x+%2B+1%29%2F%28x-3%29=x+%2B+6 remainder 19


You can use this online polynomial division calculator to check your work


Polynomials-and-rational-expressions/118657: 5y^3(y^5)^2
___________
10y^5(y^2)^6
1 solutions

Answer 86793 by jim_thompson5910(28504) About Me  on 2008-01-04 13:05:53 (Show Source):
You can put this solution on YOUR website!
%285y%5E3%28y%5E5%29%5E2%29%2F%2810y%5E5%28y%5E2%29%5E6%29 Start with the given expression


%285y%5E3y%5E%285%2A2%29%29%2F%2810y%5E5y%5E%282%2A6%29%29 Multiply the exponents



%285y%5E3y%5E10%29%2F%2810y%5E5y%5E12%29 Multiply


%285y%5E%283%2B10%29%29%2F%2810y%5E%285%2B12%29%29 Multiply the monomials by adding the exponents


%285y%5E13%29%2F%2810y%5E17%29 Add


5y%5E%2813-17%29%2F10 Now divide the monomials by subtracting the exponents



5y%5E%28-4%29%2F10 Subtract


y%5E%28-4%29%2F2 Now reduce 5%2F10 to get 1%2F2



1%2F2y%5E4 Now rewrite y%5E%28-4%29 as 1%2Fy%5E4


So %285y%5E3%28y%5E5%29%5E2%29%2F%2810y%5E5%28y%5E2%29%5E6%29 simplifies to 1%2F2y%5E4.


In other words, %285y%5E3%28y%5E5%29%5E2%29%2F%2810y%5E5%28y%5E2%29%5E6%29=1%2F2y%5E4


Quadratic_Equations/118664: explain why a^0 =1 for any nonzero value of a.
1 solutions

Answer 86791 by jim_thompson5910(28504) About Me  on 2008-01-04 12:57:07 (Show Source):
You can put this solution on YOUR website!
Remember, when you multiply expressions like x%5E3 and x%5E2, you simply add the exponents. So x%5E3%2Ax%5E2=x%5E%283%2B2%29=x%5E5

Now when you divide, just undo the multiplication by dividing. In other words, x%5E3%2Fx%5E2=x%5E%283-2%29=x%5E1=x

Now if you divide 2 equal expressions, then you will always get 1 (ie x%2Fx=1). So something like x%5E3%2Fx%5E3=x%5E%283-3%29=x%5E0=1

So this shows why a%5E0+=1 for any nonzero value of a. Now I'll let you think this question over: why does "a" have to be nonzero?


Complex_Numbers/118661: what is the difference of two squares mean
1 solutions

Answer 86789 by jim_thompson5910(28504) About Me  on 2008-01-04 12:11:10 (Show Source):
You can put this solution on YOUR website!
In this case, a square is a term that is squared. For instance, the variable x is a term and x%5E2 is a square. So if we have x and y, then x%5E2 and y%5E2 are both squares. Now subtract one from the other to get a difference of squares: x%5E2-y%5E2


note: this also works for numbers. For instance, 25 is a perfect square that can be written as 5%5E2. So if we have x%5E2-25 it's the same as x%5E2-5%5E2 which is also a difference of squares.