SOLUTION: 2m + n = 1 m - n = 8

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Question 180671This question is from textbook Algebra 1
: 2m + n = 1
m - n = 8 This question is from textbook Algebra 1

Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
There are 2 equations and 2 unknowns,
so it is solvable. If there were more
unknowns than equations it would be
unsolvable
(1) 2m+%2B+n+=+1
(2) m+-+n+=+8
Just add the equations
2m+%2B+m+%2B+n+-+n+=+1+%2B+8
3m+=+9
Divide both sides by 3
%283m%29%2F3+=+9%2F3
m+=+3
As long as I do the same thing to both
sides, the equation is still true.
Put m+=+3 back into (2)
3+-+n+=+8
Subtract 3 from both sides
-n+=+8+-+3
-n+=+5
Multiply both sides by -1
n+=+-5
The solution is m+=+3 and n+=+-5