Step-by-step explanation:
I'll be using substitution to solve this since it's easier. Since y = 3x - 9, I can plug that into the y for the other equation and vice versa.
1.) Cancel out -2x on the right side by adding it on both sides.
2.) Cancel out -9 on left side by adding it on both sides.
3.) Divide both sides by 5 to isolate and solve for x.
4.) Plug x into one of the equations to solve for y.
5.) Solve.
Solution: (2, -3)