Question

Find the lateral area and the surface area of the regular pyramid

Answer 1

Since, it is a regular pyramid with square base having side 9 in.

The perimter of base is,

`P=4* s.`
`P=4*9`
`P=36\text{ in.}`

The base area is,

`A=s^2`
`A=9^2`
`A=81in^2`

The slant height is given as,

`l=\text{ 8 in.}`

Therefore the lateral area is,

`L=(1)/(2)* P* l`
`L=(1)/(2)*36*8`
`L=144in^2\text{.}`

The surface area of regular pyramid is, the sum of lateral area and base area.

`S=L+A`
`S=\text{ 144}+81`
`S=225in^2`

Hence the lateral area of regular pyramid is