Respuesta :

Answer:

16

Step-by-step explanation:

Sum of all angles of triangle = 180

30 + 90 + 4x - 4 = 180

30 +90 - 4 + 4x = 180

116 + 4x = 180

Subtract 116 form both sides

4x = 180 - 116

4x = 64

Divide both sides by 4

x = 64/4

x = 16