Question

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

and

Regular triangular pyramid has the slant height k=12 cm and lateral area AL = 198 cm2. Find the length of the base edge.

Answer 1

the area is three triangles, each with base 6 and height 9.
Recall that the area of a triangle is A = 1/2 bh

and

same problem, only this time, solve for b

Answer 2

81 cm

Answer 3

thanks isabella

Answer 4

no problemo