SOLUTION: solve by the substition method 9x+9y=-27 and -4x+y=22

Algebra ->  Coordinate Systems and Linear Equations  -> Lessons -> SOLUTION: solve by the substition method 9x+9y=-27 and -4x+y=22      Log On


   

Question 238509: solve by the substition method 9x+9y=-27 and -4x+y=22
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
Use eq. 2,
y=4x%2B22
Substitute into eq. 1, but simplify eq. 1 first,
9x%2B9y=-27
x%2By=-3
x%2B%284x%2B22%29=-3
5x%2B22=-3
5x=-25
x=-5
Use either eq. to find y.
y=4x%2B22
y=4%28-5%29%2B22
y=2
(x,y)=(-5,2)