SOLUTION: in elmination how would i solve this:x+2y=-9 4x+2y=6

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Question 186643: in elmination how would i solve this:x+2y=-9
4x+2y=6
Answer by nerdybill(7384) About Me  (Show Source):
You can put this solution on YOUR website!
x+2y=-9
4x+2y=6
.
Multiply both sides of top equation by -1:
-x-2y=9
4x+2y=6
.
Now, add the two equation together:
-x-2y=9
4x+2y=6
-------
3x =18
x = 6 (solution for x)
.
Substitute the above back into the original top equation and solve for y:
x+2y=-9
6+2y=-9
2y=-15
y=-15/2 (solution for y)