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Solve the system by substitution.

-y = x
-3x + 3y = -36

**the answer is a point on a line (x,y).

User EdwinW
by
6.4k points

1 Answer

5 votes

Answer:

I gave you most of the answer. I'll let you check my work and find the point using the solution.

Explanation:

The first thing we do is we divide by negative one in the first equation to get

y = -x.

-3x + 3y = -36

Plug in y = -x and get

-3x + 3(-x) = -36

= -3x - 3x = -36

This equals -6x = -36

divide both sides by -6 and you get 6. 6 is your x value

Plug 6 back in to the second equation.

-3x + 3y = -36

-3(6) + 3y = -36

-18 + 3y = -36

3y = -18

y = -6

User Trent Scholl
by
6.2k points
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