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Question 237112: please help me solve this equation.
i have to use substitution or elimination to solve each system or equations.
9x+2y=5
3x-y=-10
Answer by HeyEv(4)   (Show Source):
You can put this solution on YOUR website! I am going to use elimination, because it seems faster for this problem.
I want to get rid of Y. We already have a 2y, so to get -2y we are going to multiply the second system by 2
9x+2y=5
2(3x-y=-10)
_________
9x+2y=5
6x-2y=-20
__________
Next, we add and eliminate;
15x=-15
x= -1
_____
Now, we plug it in.
9*(-1)+2y=5
-9+2y=5
2y=14
y=7
and we check!
9x+2y=5
9(-1)+2(7)=5
-9+14=5
5=5,CORRECT!
_________
3x-y=-10
3(-1)-(7)=-10
-3-7=-10
-10=-10, CORRECT!
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