Question

the base of a pyramid is equilateral triangle of side 8cm long. If the altitude of the pyramid is 15cm ,find it's volume​

Answer 1

138.56cm2

Explanation:

B.a×hx1/3

B.a=1/2×8×8sin60=27.71cm2

1/3×27.71×15=138.56cm2

Answer 2

V = 80√3 cm³

Explanation:

V = Ab×h/3

Ab = l²√3/4 = 64√3/4 = 16√3 cm²

V = 16√3cm²×15cm/3

= 16√3cm²×5cm

= 80√3 cm³