Standard difficulty · 20 questions · 40 marks
Show your working for Sections B and C. Answers are on the last page — try every question first!
Circles · AW-10M-CIR-2026-V1 · For parents — fold back or tear off before handing the sheet to your child.
| Q | Answer | Working |
|---|---|---|
| 1 | (d) 10 cm | OQ ⟂ PQ, so PQ = √(262 − 242) = 10 |
| 2 | (c) 30 cm | OP = √(242 + 182) = 30 |
| 3 | (d) 65° | ∠OAP = ∠OBP = 90°, so ∠AOB = 360° − 180° − 115° = 65° |
| 4 | (d) 18° | ∠OAP = 90°, so ∠APO = 90° − 72° = 18° |
| 5 | (a) exactly one point | — |
| 6 | (b) 96 cm | the radius to the point of contact bisects the chord: half-chord = √(502 − 142) = 48 |
| 7 | (c) 13 cm | AB + CD = BC + DA: DA = 10 + 12 − 9 = 13 |
| 8 | (a) Both A and R are true, and R is the correct explanation of A. | A is true: √(102 − 62) = 8. R is true and explains A. |
| 9 | 36 cm | √(1112 − 1052) = √1296 = 36 |
| 10 | 25° | OAPB has two right angles, so ∠APB = 180° − 155° = 25° |
| 11 | 66° | PA = PB, so △PAB is isosceles: ∠PAB = (180° − 48°)/2 |
| 12 | AP = 8 cm, BQ = 10 cm, CR = 11 cm | tangents from a point are equal: AP = AR, BP = BQ, CQ = CR; AP = (AB + CA − BC)/2 = 8 |
| 13 | 20 cm | half-chord 12; R = √(162 + 122) = 20 |
| 14 | DA = 15 cm; perimeter 68 cm | AB + CD = BC + DA; perimeter = 2(AB + CD) |
| 15 | 36 cm | r = √(452 − 272) = 36 |
| 16 | 48 cm | PA = 30; OP bisects AB at right angles, and (1/2) × OA × PA = (1/2) × OP × (AB/2), so AB = 2 × 40 × 30/50 |
| 17 | 9 m | the path is a tangent, at right angles to the radius: √(152 − 122) = 9 |
| 18 | 8 m (on both AB and AC) | the tangents from A are equal; AP = (AB + AC − BC)/2 = (35 + 32 − 51)/2 = 8 |
| 19 | OP = 17√2 cm; each tangent 17 cm | OP bisects the angle, so ∠APO = 45°; sin 45° = 17/OP and tan 45° = 17/PA |
| 20 | DA = 17 m; Rs 4,410 | AB + CD = BC + DA; perimeter = 98 m |