Solve the simultaneous equations: 12x - 4y = 12 (1) and 3x + 2y = 12 (2)

3x + 2y = 12 (2) multiply by 4 (To make the x coefficients equal for both equations)
12x + 8y = 48 (3)
(3) - (1)
12y = 36
Divide through by 12
y = 3
Sub y = 3 into equation (2)
3x + 2(3) = 12
3x + 6 = 12
3x = 6
x = 2
Check solutions: Sub y = 3 and x = 2 into equation (1)
12(2) - 4(3) = 12 = 12
This is true so the solutions are correct.