Question

Find the surface area

Answer 1

884yd²

Explanation:

Given in the question a pyramid with a square base

Slant height = 20

length of side of square = 18

Area of the figure = base area + 4(triangle area)

To calculate base area

base area of pyramid = l²

= 324 yd²

To calculate the one face of pyramid

area of one face = 1/2 (height) x (base)

= 1/2 (20)(14)

= 140

Plug values in the formula

Area of the figure = 324 + 4(140)

= 884 yd²

Answer 2

Total surface area = 1044 yd²

Explanation:

From the figure we can see a square pyramid.

Base = 18 yd

Slant height = 20 yd

To find the Base area

Total surface area = Base area + (4* area of one lateral face)

Base area = Base² = 18² = 324 yd²

To find the lateral surface area

Area of one face = bh/2

b = base = 18 yd

h = Slant height = 20 yd

Area = bh/2 = (18 * 20)/2 = 180 yd²

Lateral surface area = 4 * 180 = 720 yd²

To find the total surface area

Total surface area = 324 + 720 = 1044 yd²