The diagonals of rectangle ABCD meet at O, and $\angle AOB = 118^\circ$. What is $\angle OBC$?

Explanation

1. 01

   The diagonals of a rectangle are equal and bisect each other, so $OA = OB$.

2. 02

   In isosceles triangle AOB, $\angle OBA = (180^\circ - 118^\circ) \div 2 = 31^\circ$.

3. 03

   $\angle ABC = 90^\circ$, so $\angle OBC = 90^\circ - 31^\circ = 59^\circ$.