(a) Using a ruler and a pair of compasses only, construct:
(i) a triangle PQR such that |PQ| = 10 cm, |QR| = 7 cm and PQR = 90°;
(ii) the locus l1 of points equidistant from Q and R;
(iii) the locus l2 of points equidistant from P and Q.

(b) Locate the point O equidistant from P, Q and R.
(c) With O as centre, draw the circumcircle of the triangle PQR.
(d) Measure the radius of the circumcircle.

observation

This question tested the skills of basic construction.  Candidates were required to  construct a right angled triangle PQR, bisect PQ and QR, use the point of intersection of l1 and l2 to circumscribe the triangle.

Many candidates avoided this question.  However, the few who attempted it gave a good account of themselves.