Multiple choice

Two parallel chords of equal length 18 cm are drawn inside a circle of radius 15 cm Find the distance between the chords

  1. 12 cm

  2. 18 cm

  3. 24 cm

  4. 30 cm
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The distance from the center to a chord of length 18 cm is found using the Pythagorean theorem: sqrt(15^2 - 9^2) = sqrt(225 - 81) = sqrt(144) = 12 cm. Since the chords are on the same side, the distance between them is 12 - 0 = 12 cm, but if they are on opposite sides, it is 12 + 12 = 24 cm. Given the options, 24 cm is the intended answer.

AI explanation

The perpendicular from the centre to a chord bisects it, making the half-length of each chord 9 cm. Using the Pythagorean theorem, the distance from the centre to each chord is the square root of (15 squared minus 9 squared), which equals 12 cm. Since the parallel chords must be on opposite sides of the centre for this configuration, the total distance between them is 12 plus 12. The distance between the chords is 24 cm.

Keep practicing — related questions