Find the unknown 360 + (x-360) times 2 / 7 = 1 / 2 x (there must be a process!)

Find the unknown 360 + (x-360) times 2 / 7 = 1 / 2 x (there must be a process!)

360 + (x-360) × 2 / 7 = x / 2, multiply both sides by 14
5040+4x-1440=7x
3x=3600
x=1200