Question

Regular triangular pyramid has 6 cm long base edge and slant height k=9 cm. Find the lateral area of the pyramid.

Answer 1

Answer:

81 cm²

Step-by-step explanation:

Since, the lateral face of a triangular pyramid is a triangle,

Given,

The base edge or the base of one lateral face of pyramid, a = 6 cm,

And, the slant height or the height of the face, k = 9 cm,

Thus, the area of one lateral face of the pyramid,

$A=\frac{1}{2}\times a\times k$

$=\frac{1}{2}\times 6\times 9$

$=\frac{54}{2}$

$=27\text{ square cm}$

We know that, a Regular triangular pyramid has 3 lateral faces,

Hence, the total lateral area of the pyramid,

$L.A.=3\times\text{ The area of one lateral face}$

$=3\times 27$

$=81\text{ square cm}$

Answer 2

Answer:

hiiii your answer is 81!!

Step-by-step explanation: