4 L + 4 l + 4 h = 116, rezulta L +l +h = 29
D = radical din L patrat +l patrat + h patrat, deci D patrat = L patrat + l patrat + h patrat, adica L patrat +l patrat + h patrat = 21 patrat = 441
Aria totala este 2 L l + 2 Lh + 2 l h
Avem ( L + l + h) la patrat = L patrat + l patrat + h patrat + 2 L l +2 L h + 2 l h, de unde
Aria totala = ( L + l + h) la patrat - (L patrat + l patrat + h patrat )=
= 29 patrat - 441 = 841 - 441 =
= 400