Respuesta :

Answer:

x = 13.5°

Step-by-step explanation:

Angles 2 + 3 = a straight line, so 180°

180 - 66 = 114 = angle 2

114 = 10x - 21

114 + 21 = 10x

135 = 10x

135 / 10 = x

13.5 = x