Question

Base area of square pyramid is 100 square centimetres and its lateral surface area is 260 square centimetres. (a) Find the total surface area of the square pyramid. (b) Find the length of base edge. (c) Find the slant height. (d) Find the volume of square pyramid.​

Answer 1

Answer:

b) base area of a square pyramid =100cm^2

=>s^2 = 100

=> s = √100 = 10cm

LSA of square pyramid = 4s × l/2

where l is slant height and s is side of a square

=> 260 = 40 × l / 2

=> l = 13cm

we have a relation,

l^2 = r^2 + h^2

=> 169 = (10/2)^2 + h^2

=> 144 = h^2

=> h = 12cm

(a) TSA of square pyramid = LSA + area of base

we have LSA = 260sq.cm

then TSA = 260 + 10^2 = 360sq.cm

d) volume of square pyramid = area of base ×

height /3

= s^2 × 12 / 3 = 100× 4 = 400 cubic.cm

hope it helps u!!!!!☺️☺️