Question

Find the surface area of a pentagon-based pyramid with slant height of 11 m.

Apothem of the pentagon = 3.5 m

Answer 1

108.75 square meter.

Explanation:

Surface area of pentagon based pyramid:

`\sf \boxed{\text{\bf Surface area of pentagonal pyramid = $ \bf (5)/(2)*b*(a + s)$}}`

Here, b is the base length of the pyramid. b = 3 m

a is the apothem of the pyramid. a = 3.5 m

s is the slant height of the pyramid. s = 11 m

`\sf Surface \ area = (5)/(2)*3*(11 + 3.5)`

`\sf = (5)/(2)*3*14.5\\\\ = 108.75 \ m^2`