Question

A tangent is drawn from a point at a distance of 17 cm of circle C(0, r) of radius 8 cm. The length of its tangent is ______

Options

• 5 cm

• 9 cm

• 15 cm

• 23 cm

Answer 1

A tangent is drawn from a point at a distance of 17 cm of circle C(0, r) of radius 8 cm. The length of its tangent is 15 cm.

Explanation:

In ∆OAP, AP² + OA² = OP²

⇒ AP² + (8)² = (17)²

⇒ AP² + 64 = 289

⇒ AP² = 289 – 64 = 225

∴ AP = `sqrt225` = 15 cm