SOLUTION: from the following two equations: 3a-2b=11 5a+7b=39 find a and b

Algebra ->  Equations -> SOLUTION: from the following two equations: 3a-2b=11 5a+7b=39 find a and b      Log On


   

Question 1015938: from the following two equations:

3a-2b=11
5a+7b=39
find a and b
Answer by FrankM(1040) About Me  (Show Source):
You can put this solution on YOUR website!
3a-2b=11
5a+7b=39
multiply 1st equation by 5 and second by 3.
15a-10b=55
15a+21b=117
flip signs on first equation and add -
-15a+10b=-55
15a+21b=117
____________________
31B = 62
B=2
3A-2(2)=11
3A-4=11
3A=15
A=5