Question

A regular triangular pyramid has a base area of 31.5 mm2 and a surface area of

Answer 1

Answer:

A) 220.5 mm^2

Step-by-step explanation:

Explanation:-

Given A regular triangular pyramid has a base of area is 31.5mm^2

and also given surface area of triangular pyramid is 252 mm ^2

by using formula

surface area of  regular triangular pyramid = base of area + half of lateral surface.

$surface area = area of the pyramid X \frac{1}{2} lateral surface$

252 = 31.5 + $\frac{1}{2} lateral surface$

$252-31.5= \frac{1}{2} lateral surface$

220.5 = lateral area of triangular pyramid

lateral area of triangular pyramid = 220.5 mm^2