Question

Un paralelipiped dreptunghic,are diagonala de 16 cm si aria totala de 420 cm. se cere:suma dimensiunilor paralelipipedului.

Answer 1

$(L+l+h)^{2} =L^{2} + l^{2}+ h^{2}+2(Ll+ Lh+lh)$
$d^{2} = L^{2} + l^{2}+ h^{2}=256 \\ A_{t} =2(Ll+Lh+lh)=420$
$(L+l+h)^{2}=256+420=676 \\ L+l+h= \sqrt{676} =26$