Respuesta :

Answer:

x = 10

Step-by-step explanation:

Both angle A and are corresponding angles.

∠A = ∠B

9x - 40 = 3x + 20

9x = 3x + 20 + 40

9x - 3x = 20 + 40

6x = 60

x = 60/6

x = 10

x = [10]