Equation 1) 3x = 9 - 6y
Equation 2) 3x + 8y = 9
Add 6y to both sides in equation #1.
1) 3x + 6y = 9
2) 3x + 8y = 9
Subtract equations from one another.
-2y = 0
Divide both sides by -2.
y = 0
Plug in 0 for y in the first equation.
3x = 9 - 6y
3x = 9 - 6(0)
Simplify.
3x = 9 - 0
Simplify.
3x = 9
Divide both sides by 3.
x = 3
So, x = 3, y = 0
~Hope I helped!~