X - 2 = X - 4 -------- -------- X + 2 = X + 4

x - 2 x - 4
---------- = ---------
x + 2 x + 4
( x - 2 ) x ( x + 4 )= ( x - 4 ) x ( x + 2 )
x² + 4x - 2x - 8 = x² + 2x - 4x - 8
4x - 2x = 2x - 4x
2x = 2x - 4x
-4x = 0
x = 0