SOLUTION: Plz help.. need to solve by the substitution method.. what is the solution 8m + n=1 m - 8n=57

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Question 237442: Plz help.. need to solve by the substitution method.. what is the solution
8m + n=1
m - 8n=57
Answer by College Student(505) About Me  (Show Source):
You can put this solution on YOUR website!
Steps:
a. leave the first equation alone for now.
b. solve for one of the variables using the second equation. Let's solve for m.
c. then use the value of m and substitute it in the first equation to solve for the other variable.
Problem:
m-8n=57
m=57%2B8n
Now use this value and plug it in the first equation.
8m%2Bn=1
8%2857%2B8n%29%2Bn=1
456%2B64n%2Bn=1
65n=1-456
n=-455%2F65
n=-7
Now, we look for the exact value of m.
m=57%2B8n
m=57%2B8%28-7%29
m=57-56
m=1
Your values are: n=-7 and m=1
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If you need to check your answers (some professors do ask you to do it), just substitute these two values in the original equations to comfirm they add up correctly. This is good to do it to ensure you didn't miss any negatives when you worked out your problem.