Question

Un pararelipiped dreptunghic ABCDA'B'C'D' cu baza ABCD are Al=56cm2, At=200cm2, AB=8cm. Calculati:
a) aria bazei pararelipipedului
b) lungimea segmentulu [BC]
c) inaltimea pararelipipedului
d) volumul pararelipipedului.

Answer 1

al=56 cm^2
al=p*h=2(L+l)*h=56
at=2*ab+al=200 => ab=(at-al)/2 <=> ab=(200-56)/2 => ab=72 si ab=L*l, unde L=AB=8
=> 8*l=72 => l=72/8 => l=9 (=BC)
at=2*ab+al <=> at=2*(l+l)*h+2*L*l <=> 2*(8+9)*h+2*8*9=200
<=> 34*h+144=200 => 34*h=56 => h=56/34 =28/17 (s-ar putea sa fie gresite datele problemei) => V=ab*h=72* 28/17= 118.56