SOLUTION: Solve by Substitution method 9m+n=32 m-3n=16

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Question 325978: Solve by Substitution method
9m+n=32
m-3n=16
Answer by mananth(16946) About Me  (Show Source):
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9m+n=32...........1
m-3n=16...........2
..
multiply equation by 3 and it to equation 2
3(9m+n)+(m-3n)=32*3+16
27m+3n+m-3n=96+16
28m=112
divide by 28
28m/28=112/28
m=4
..
plug the value of m in the equation 2
4-3n=16
Add -4 on both sides
4-4-3n=16-4
-3n=12
divide by -3
-3n/-3 = 12/-3
n=-4