Question

Suppose ABCD is a rectangle whose diagonals AC and BD intersect at O. If angle OAB = 62' , find angle OBC.

Answer 1

OAB = OBA = 62 deg.  As OAB is an isosceles triangle, as  OA = OB = 1/2 *√(a²+b²)

OBC = 90 - OBA = 90  - 62 = 28 deg.