Question

Piramida triunghiulara reg are latura bazei de lungime egala cu 12 cm si muchia laterala de lungime 10
Calculati
a) apotema piramidej
b) apotema bazei
c) inaltimea piramidei
d) aria lat
e)aria totala a piramidei
f) volumul piramidei

Answer 1

L=12
muchia=10
L/2=6
a) apotema piramidei=√(10²-6²)=√(100-36)=√64=8 cm
b)apotema bazei =L√3/6=12√3/6=2√3 cm
c)inaltimea piramidei= √(12²-6²)=√(144-36)=√108=6√3 cm
d)Aria laterala=Pb×apotema piramidei/2 =3×12×8/2=144 cm²
e)Aria totala a piramidei=Al+Abazei=144+36√3=36(4+√3) cm²
Abazei=L²√3/4=144√3/4=36√3 cm²
f)Volumul piramidei=Abazei×h/3=36√3 × 6√3/3=216 cm³