y=-3x
5x+ 3(-3x) = 12
5x-9x=12
-4x=12
x=-3
y=-3*(-3) = 9
y=-3x}
5x+3y=12
5x+3*(-3x)=12 y=-3*(-3)
5x-9x=12 y=9
x=12:(-4)
y=-3x
5x+ 3(-3x) = 12
5x-9x=12
-4x=12
x=-3
y=-3*(-3) = 9
y=-3x}
5x+3y=12
5x+3*(-3x)=12 y=-3*(-3)
5x-9x=12 y=9
-4x=12
x=12:(-4)
x=-3