Identify the given angles and the angle to be found.

The points P, Q, R, S, T lie on a circle.
We are given:
$\angle QPT = 85^\circ$
$\angle RQS = 25^\circ$
We need to find $x = \angle TBQ$.
Point B is the intersection of chords PS and TQ.

An inscribed angle is half the measure of its intercepted arc. Conversely, angles subtended by the same arc are equal.

• $\angle QPT = 85^\circ$. This angle subtends arc QT.
• $\angle RQS = 25^\circ$. This angle subtends arc RS