SOLUTION: Use the Substitution method to solve the system of equations. x + y = -4 x - y = 2

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Question 329747: Use the Substitution method to solve the system of equations. x + y = -4 x - y = 2
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
ELimination:
Add the equations together.
x+%2B+y+%2B+x+-+y+=-4%2B+2
2x=-2
highlight%28x=-1%29
.
.
.
Then use either equation to solve for y.
-1%2By=-4
highlight%28y=-3%29
.
.
.
Substitution:
From eq. 1,
y=-x-4
Substitute into eq. 2,
x-%28-x-4%29=2
x%2Bx%2B4=2
2x=-2
highlight_green%28x=-1%29
Then from above,
y=1-4
highlight_green%28y=-3%29