Respuesta :

sqdancefan

9514 1404 393

Answer:

  x = 10

Step-by-step explanation:

The marked angles are "alternate interior" angles, so are congruent.

  (x° +20°) = (4x° -10°)

  30 = 3x . . . . . . . . . . . . . . . divide by °, add 10-x

  10 = x . . . . . . divide by 3