SOLUTION: 12x+18y=30 4x-13y=67 ; please solve the system of equation.

Algebra ->  Equations -> SOLUTION: 12x+18y=30 4x-13y=67 ; please solve the system of equation.      Log On


   

Question 179338This question is from textbook
: 12x+18y=30 4x-13y=67 ; please solve the system of equation. This question is from textbook

Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
1.12x%2B18y=30
2.4x-13y=67
Multiply eq. 2 by (3) and subtract it from eq. 1,
%2812x%2B18y%29-3%284x-13y%29=30-3%2867%29
12x%2B18y-12x%2B39y=-171
57y=-171
highlight%28+y=-3%29
Now use either eq. 1 or eq. 2 to solve for x,
1.12x%2B18y=30
12x%2B18%28-3%29=30
12x-54=30
12x=84
highlight%28+x=7%29