SOLUTION: -5m+6n=-8 -m+3n=-7 how would you solve this using elimatiob by addition?

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Question 461793: -5m+6n=-8
-m+3n=-7
how would you solve this using elimatiob by addition?
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!


solve this using elimatiob by addition
-5m%2B6n=-8..........1
-m%2B3n=-7}..........2.....both sides multiply by -2
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-5m%2B6n=-8..........1
-m%28-2%29%2B3n%28-2%29=-7%28-2%29}..........2
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-5m%2B6n=-8..........1
2m-6n=14}..........2..........add 1 and 2
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-5m%2B2m%2B6n-6n=-8%2B14
-3m%2Bcross%286n%29-cross%286n%29=6
-3m=6
m=6%2F-3
m=-2..........now find n

-5m%2B6n=-8..........1...plug in m=-2
-5%28-2%29%2B6n=-8..........1

10%2B6n=-8
6n=-8-10
6n=-18
n=-18%2F6
n=-3

check:
-5m%2B6n=-8..........1...plug in m=-2 and n=-3
-5%28-2%29%2B6%28-3%29=-8
10-18=-8
-8=-8