Perpendicular height of a cone is 12 cm and its slant height is 13 cm. Find the radius of the base of the cone.

Question

Philoid · Accepted Answer

We have

Given that, height of cone = 12 cm and slant height of cone = 13 cm.

We need to find radius of the base of the cone, r.

In right-angled ∆AOB, using Pythagoras theorem,

AB² = AO² + OB²

⇒ OB² = AB² – AO²

⇒ r² = 13² – 12²

⇒ r² = 169 – 144 = 25

⇒ r = √25

⇒ r = 5

Thus, radius of the base of the cone is 5 cm.