You'll need to solve a 2 equation formula. Here's a simpler example.
- 2x + 3y = 7
- x + 2y = 4
First you need to make it so both equation has the same number of y's:
- 4x + 6y = 14
- 3x + 6y = 12
Then subtract both equations
- (4 - 3)x + (6 - 6)y = (14 - 12)
Which means
- x = 2