Respuesta :

Answer:

x= 30

Step-by-step explanation:

angle AOB= 180- 4x

angle AOC is a right angle because OA is perpendicular to OC

180- 4x + x = 90 degrees

180- 3x = 90 degree

180- 90 = 3x

90= 3x

therefore x= 90/3= 30