10. Circles Class 9 Mathematics NCERT Exemplar Solutions (CBSE)

Chapter 10: Circles – Class 9 Mathematics NCERT Exemplar Solutions (CBSE Board)

Chapter 10: Circles

EXERCISE 10.1
1. AD is a diameter of a circle and AB is a chord. If AD = 34 cm, AB = 30 cm, the distance of AB from the centre of the circle is :
(A) 17 cm (B) 15 cm (C) 4 cm (D) 8 cm
2. In Fig. 10.3, if OA = 5 cm, AB = 8 cm and OD is perpendicular to AB, then CD is equal to:
(A) 2 cm (B) 3 cm (C) 4 cm (D) 5 cm
3. If AB = 12 cm, BC = 16 cm and AB is perpendicular to BC, then the radius of the circle passing through
the points A, B and C is :
(A) 6 cm         (B) 8 cm         (C) 10 cm          (D) 12 cm
4. In Fig.10.4, if ∠ABC = 20°, then ∠AOC is equal to:
(A) 20°           (B) 40°           (C) 60°        (D) 10°

5. In Fig.10.5, if AOB is a diameter of the circle and AC = BC, then ∠CAB is equal to:
(A) 30°      (B) 60°       (C) 90°      (D) 45°

6. In Fig. 10.6, if ∠OAB = 40° , then ∠ACB is equal to :
(A) 50°      (B) 40°       (C) 60°    (D) 70°
Fig. 10.6
7. In Fig. 10.7, if ∠DAB = 60° , ∠ABD = 50° , then ∠ACB is equal to:
(A) 60°        (B) 50°       (C) 70°      (D) 80°

8. ABCD is a cyclic quadrilateral such that AB is a diameter of the circle circumscribing it and ∠ADC = 140°, then ∠BAC is equal to:
(A) 80°           (B) 50°           (C) 40°        (D) 30°
9. In Fig. 10.8, BC is a diameter of the circle and ∠BAO = 60° . Then ∠ADC is equal to :
     (A) 30°     (B) 45°        (C) 60°    (D) 120°

10. In Fig. 10.9, ∠AOB = 90° and ∠ABC = 30° , then ∠CAO is equal to:
    (A) 30°       (B) 45°       (C) 90°            (D) 60°

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Posted 4 months ago