A cone of radius 8 cm has curved surface area 136π cm². Find its height.

15 cm. 8l = 136 → l = 17 cm. h = √(17² − 8²) = √(289 − 64) = √225 = 15 cm. (√353 adds the squares instead of subtracting.)

A cone of radius 8 cm has curved surface area 136π $cm^{2}$ . Find its height.

Class 9Surface Area of a ConeMensuration

8 l = 136

→

l = 17

cm.

h

= √

(1 7^{2} - 8^{2}) =

√(289 − 64) = √225 = 15 cm. (√353 adds the squares instead of subtracting.)

Answer: B) 15 cm

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