SOLUTION: 9-4(7x-8x)=x-3 how does x = -4 i don't understand how to get to the answer

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Question 251142: 9-4(7x-8x)=x-3
how does x = -4
i don't understand how to get to the answer
Found 2 solutions by Edwin McCravy, JimboP1977:
Answer by Edwin McCravy(20060) About Me  (Show Source):
You can put this solution on YOUR website!
9-4%287x-8x%29=x-3

First do the %287x-8x%29 and get %28-1x%29

and put that in place of the %287x-8x%29

9-4%28-1x%29=x-3

Next multiply the -4%28-1x%29 and get %22%22%2B4x
and put that in place of -4%28-1x%29

9%2B4x=x-3

Now add -9 to both sides of the equation:

9%2B4x-9=x-3-9

The 9 and the -9 cancel out on the left and just leave
4x on the left. Replace the -3-9 by -12 on the right.

4x=x-12

Add -x to both sides

4x-x=x-12-x

Replace the 4x-x on the left by 3x.
The x and the -x cancel on the right,
and you have

3x=-12

Divide both sides by 3

%283x%29%2F3=%28-12%29%2F3

The 3's cancel on the right, and dividing
-12 by 3 gives -4

%28cross%283%29x%29%2Fcross%283%29=-4

or

x=-4

Edwin

Answer by JimboP1977(311) About Me  (Show Source):
You can put this solution on YOUR website!
Do the brackets first. 9-4%28-x%29=x-3
9-%28-4x%29=x-3 multiply out by 4
9%2B4x=x-3 minus a minus is a plus
9%2B3x=-3take away x from both sides
3x=-12take away 9 from both sides
x=-4divide both sides by 3