Question

Aria bazei unei piramide triunghiulare regulate este egala cu 9√3 cm² iar apotema piramidei cu 5 cm . Aflati aria laterala a piramidei.

Answer 1

Al=$\frac{3*l*ap}{2}$
$A_b$=$\frac{l^{2}√3 }{4}$ 
9√3=$\frac{l^{2}√3 }{4}$
l²√3=4×9√3
l²√3=36√3 |÷√3
l²=36
l=√36
l=6
$A_l$=$\frac{3*6*5}{2}$=$\frac{90}{2}$=45