9.1 In the diagram, O is the centre of the circle. Points S, T and R lie on the circle. Chords ST, SR and TR are drawn in the circle. QS is a tangent to the circle at S.
Use the diagram to prove the theorem which states that QST = R. (5)
9.2 Chord QN bisects MNP and intersects chord MP at S. The tangent at P meets MN produced at R such that QN || PR. Let P1 = x .
9.2.1 Determine the following angles in terms of x. Give reasons
(a) N2 (2)
(b) Qz (2)
9.2.2 Prove, giving reasons, that 
(6)
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