Respuesta :

9514 1404 393

Answer:

  x = -6

Step-by-step explanation:

The three marked angles total 180°, the number of degrees in a semicircle.

  (x +51) +65 +70 = 180

  x = 180 -186 = -6 . . . . . . . . subtract 186 and simplify

The value of x is -6.