Equation 1) y = 18 - 3x
Equation 2) -2x - 4y = 8
Rearrange equation 1.
1) 3x + y = 18
2) -2x - 4y = 8
Multiply equation 1 by 4.
1) 4(3x + y = 18)
1) 12x + 4y = 72
2) -2x - 4y = 8
Add equations together.
10x = 80
x = 10
Plug in 10 for x in first equation.
y = 18 - 3x
y = 18 - 3(10)
Simplify.
y = 18 - 30
y = -12
(10, -12)
~Hope I helped!~