SOLUTION: How do I solve by addition method? 12x-11y=-31 5x+7y=45

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Question 214650: How do I solve by addition method?
12x-11y=-31
5x+7y=45
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
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How do I solve by addition method?
12x - 11y = -31
5x + 7y = 45
:
Multiply the 1st equation by -5
Multiply the 2nd equation by 12
:
-60x + 55y = 155
+60x + 84y = 540
-------------------addition eliminates x
139y = 695
y = 695%2F139
y = 5
:
Use the 2nd equation to find x, substitute 5 for y:
5x + 7(5) = 45
5x + 35 = 45
5x = 45 - 35
5x = 10
x = 10%2F5
x = 2
:
:
Check solutions in the 1st equation
12(2) - 11(5) =
24 - 55 = -31