Question

AB is diameter and angle ACD= 55 degrees what is the measurement of angle DOB​

Answer 1

70°

Step-by-step explanation:

Angle ACD and Angle AOB are the angles on circumstance and at center respectively both lie on same arc AD

so AOD= 2× ACD = 2×55° = 110°

angleAOD and BOD angles on straight linea ngle AOD+ angle BOD = 180°So Angle BOD = 180° - 110° = 70°