Angle to chord

Weekly Problem 23 - 2008
A triangle has been drawn inside this circle. Can you find the length of the chord it forms?

Problem



$P$, $Q$ and $R$ are points on the circumference of a circle of radius 4cm. $\angle PQR=45^o$. What is the length of chord $PR$?

 

Image
Angle to Chord

If you liked this problem, here is an NRICH task which challenges you to use similar mathematical ideas.