Respuesta :

Answer:

12 - x = 20 - 5x

Add 5x on both sides,

12 - x + 5x = 20 - 5x

12 + 4x = 20

Subtract 12 on both sides,

12 - 12 + 4x = 20 - 12

4x = 8

Divide 4 on both sides,

4x / 4 = 8 / 4

x = 2

Hence proved.