Question

O is the centre of a circle. AC and BD are two chords of the circle intersecting each other at P. if L AOB = 15 degree and L APB = 30 degree then L COD is equal to​

Answer 1

Answer: 45

Explanation:

AOB = 2ADB because tge central angle is twice as big as an inscribed angle thatrests on the same arc of a circle rests on the same arc of a circle. That means that ADB = 7.5. We know that for triangle APD, the exterior angle is equal to the sum of the other two interior angles, so APB = PDA + PAD. PAD = 30 - 7.5 = 22.5; this angle rests on the arc CD, so COD = 22.5 * 2 = 45.