Question

Aflati lungimile laturilor unui paralelogram ABCD stiind ca are perimetrul egal cu 40 cm iar AB = 3·BC. rezolvare completa.

Answer 1

AB=3*BC
P=40
P=2*AB+2*BC
40=2*AB+2*BC
unde AB=3*BC
40=2*3*BC+2*AB
40=6BC+2*AB
40=8*BC=BC=40/8=5
deci AB=3*5
AB=15 cm
BC=5 cm

Answer 2

P=2(L+l)
2(3BC+BC)=40 cm
4BC=40 cm/2
4BC=20 cm
BC=20 cm/4
BC=5 cm=>AB=3*5 cm=15 cm