Question

X=y-8
-x-y=0
how many solutions
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Answer 1

1(-4,4)

Explanation:

The first step I did was make these equations more graphable, making x=y-8 into x+8=y and -x=y. Then I had graphed these two, and observed the intersection they made. Also another way is using algebra, you can turn x=y-8 into x-y+8=0, and then x-y+8=-x-y, using that we can find -4 = x, and y = 4, that would be the only solution.

Answer 2

one solution

Explanation:

x=y-8

-x-y=0

Substitute the first equation into the second equation

-(y-8) -y =0

-y +8 -y =0

-2y +8 = 0

Add 2y to each side

-2y+2y +8 = 2y

8 = 2y

Divide each side by 2

8/2 = 2y/2

4 =y

x = y-8

x = 4-8

x=-4

(-4,4)

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