JAMB 2017 · UTME · Q36

In the figure, determine the angle marked $y$ .

Worked solution (try it first)

Angles in triangle $PQT$ add up to $180^\circ$ : $\angle PTQ = 180^\circ - 44^\circ - 70^\circ$
$= 66^\circ$ .
$PTS$ is a straight line, so $\angle PTQ$ is the exterior angle of the cyclic quadrilateral $QRST$ at $T$ .
The exterior angle of a cyclic quadrilateral equals the interior opposite angle, which is at $R$ .
So $y = 66^\circ$ , option A.