Respuesta :

Judging by the answer choices, you require ∠1 = ∠2 for the lines to be parallel. That means
  20 - 8x = 30 - 16x
  8x = 10 . . . . . . . . . . . add 16x-20
  x = 10/8 = 1.25

The appropriate choice is
  b. 1.25