The length of a chord which is at a distance of 5 cm from

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The length of a chord which is at a distance of 5 cm from the centre of a circle of radius 13 cm is :

1. 18 cm.
2. 24 cm.
3. 25 cm.
4. 30 cm.

Correct Option: B

On the basis of question we draw a figure of a circle with centre O

Here , OC = 5 cm.
OC ⊥ AB
∴ AC = CB
OA = 13 cm.
In ∆ OAC,
AC = √OA² - OC²
AC = √13² - 5²
AC = √169 - 25
AC = √144 = 12 cm.
∴ AB = 2 AC = 2 × 12 = 24 cm.