Plug in y into -4x+3y=-17 -4x+3 (1-2x)=-17 -4x+3-6x=-17 -10x+3=-17 -3 both sides -10x=-20 ÷-10 both sides x=2 plug in x to find y y=1-2 (2) y=1-4 y=-3
x+3y=9 2x+3y=15
make first equation into x= form -3y both sides x=-3y+9 2x+3y=15 plug in x into 2x+3y=15 2 (-3y+9)+3y=15 -6y+18+3y=15 -3y+18=15 -18 both sides -3y=-3 ÷-3 both sides y=1 plug in y x+3 (1)=9 x+3=9 -3 both sides x=6
