passwella.
Menu

JAMB Mathematics 1986 Question 40

Question 40

Angles and Polygons

In the figure above ΔPQT is isosceles. PQ = QT. SRQ = 35°, TPQ = 20° and PQR is a straight line. Calculate TSR.

Diagram for this question
  1. A.20°
  2. B.55°
  3. C.75°
  4. D.140°.
Show the answer and explanation

Answer: C (75°)

Explanation

<QTP = 20° too, so <PQT = 140° and <TQR = 40°. In triangle SQR, <QSR = 180° − 40° − 35° = 105°, so <TSR = 180° − 105° = 75°.