Question

Un cub are diagonala unei fete egale cu 16 cm.Aflati.
a)lungimea muciei cubului
b)aria laterala a cubului
c)aria totala a cubului
Va rog e urgent!!!

Answer 1

$d=16 \ cm \\ d^2=l^2+l^2 \\ 2l^2=16^2 \\ l^2= \frac{256}{2} \\ l^2=128 \\ l=\sqrt{128} \\ \boxed{l=8\sqrt2 \ cm} \\ A_l=4l^2 \\ A_l=4 \cdot 128 \ cm^2 \\ \boxed{A_l=512 \ cm^2}\\ A_t=6l^2 \\ A_t=6 \cdot 128 \ cm^2 \\ \boxed{A_t=768 \ cm^2}$