Multiple choice

A 9 cm long perpendicular is drawn from the centre of circle to a chord of length 24 cm. The radius of the circle is:

  1. 20 cm

  2. 15 cm

  3. 12 cm

  4. 18 cm

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Perpendicular from center to chord bisects the chord. Half chord = 12 cm. In right triangle with perpendicular (9 cm), half-chord (12 cm) and radius (r): r² = 9² + 12² = 81 + 144 = 225. Therefore r = 15 cm.