Question

HELP PLEASE, QUICKLY!!!!!

what is the lateral area of this regular octagonal pyramid?
149.3 cm
182.9 cm
211.2 cm
298.7 cm
​

Answer 1

The answer is 298.7 cm²

Answer 2

The lateral area is
`298.7\ units^(2)`

Explanation:

we know that

The lateral area of the regular octagonal pyramid is equal to the area of its eight triangular lateral faces

The lateral area is equal to

`LA=8[(1)/(2)(b)(l)]`

we have

`b=6.6\ cm`

To find the slant height apply the Pythagoras Theorem

`l^(2)=8^(2) +8^(2)\\l^(2)=128\\l=√(128)\ units`

Find the lateral area

substitute the values

`LA=8[(1)/(2)(6.6)(√(128))]=298.7\ units^(2)`