Respuesta :

9514 1404 393

Answer:

  20

Step-by-step explanation:

The two angles shown are complementary. The corner angles in a rectangle are right angles: 90°.

  (4x -12) +(x +2) = 90

  5x = 100 . . . . . . collect terms, add 10

  x = 20 . . . . . . . . divide by 5