Question

In the figure ∠C= 40°,∠OBC=15°
Find ∠AOB
Find ∠OAB
Find all angles of triangle ABC

Answer 1

Step-by-step explanation:

$< oca = x$

c is the center of the circle

$< oac = x$

$< abc = < acb \\ ab = ac \\ therefor < oca + < ab = 90degree$