Respuesta :

Answer:

x = - 10

Step-by-step explanation:

7x + 40 = 5x + 20

7x + 40 - 40 = 5x + 20 - 40

7x = 5x - 20

7x - 5x = 5x - 5x - 20

2x = - 20

2x ÷ 2 = - 20 ÷ 2

x = - 10