SOLUTION: I'm 46 and am trying to refresh my algebra.... How would I solve this by using substitution or the addition-or- subtraction method? 2m=n-3 3m=2n-9 Thanks

Algebra ->  Equations -> SOLUTION: I'm 46 and am trying to refresh my algebra.... How would I solve this by using substitution or the addition-or- subtraction method? 2m=n-3 3m=2n-9 Thanks       Log On


   

Question 459938: I'm 46 and am trying to refresh my algebra....
How would I solve this by using substitution or the addition-or- subtraction method?
2m=n-3
3m=2n-9
Thanks
Found 2 solutions by Gogonati, richwmiller:
Answer by Gogonati(855) About Me  (Show Source):
You can put this solution on YOUR website!
Multiply the first equation by -2 and get:
system%28-4m=-2n%2B6%2C+3m=2n-9%29, add two equations to eliminate n.
-m=-3 or m=3. Now plug in the first equation m=3 to find n=?
2%2A3=n-3 solving this equation we get n=9
Answer: The solution of the system is the ordered pair (3, 9).

Answer by richwmiller(17219) About Me  (Show Source):
You can put this solution on YOUR website!
m=3 n=9
2m=n-3
3m=2n-9
substitution
n=2m+3
3m=2(2m+3)-9
3m=4m+6-9
3m=4m-3
0=m-3
3=m
2*3=n-3
6=n-3
9=n

check
6=9-3
6=6
9=18-9
9=9
ok