ABCD is a cyclic quadrilateral with $\angle B = (3x + 5)^\circ$ and $\angle D = (2x + 25)^\circ$. What is $\angle D$?

Explanation

1. 01

   Opposite angles of a cyclic quadrilateral add up to 180°: $(3x + 5) + (2x + 25) = 180$.

2. 02

   $5x + 30 = 180$, so $x = 30$.

3. 03

   $\angle D = 2 \times 30 + 25 = 85^\circ$. ($\angle B = 95^\circ$, and $85 + 95 = 180$.)