Solve this system of equations for x and y in terms of a and b. \
y - 3x = a
x = 2y + 3x + b
Multiply the first equation by 2:
2y - 6x = 2a (1)
Subtract x and b from both sides of the second equation and rewrite as:
2y + 2x = -b (2)
Subtract (1) from (2)
8x = -b - 2a (3)
Multiply (2) by 3:
6y + 6x = -3b (4)
Add (1) and (4)
8y = 2a - 3b (5)
You can now divide (3) by 8 to get x and (5) by 8 to get y