SOLUTION: Solve by the Elimination method 2a+3b=7, -2a+b=13

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Question 712193: Solve by the Elimination method 2a+3b=7, -2a+b=13
Answer by checkley79(3341) About Me  (Show Source):
You can put this solution on YOUR website!
2a+3b=7
-2a+b=13 add
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4b=20
b=20/4
b=5 ans.
2a+3*5=7
2a+15=7
2a=7-15
2a=-8
a=-8/2
a=-4 ans.
Proof:
-2*-4+5=13
8+5=13
13=13