Răspuns :
L+L+l+l=420
L=4l
4l+4l+l+l=420
10l=420
l=420:10
l=42
L=4*42
l=168
L=4l
4l+4l+l+l=420
10l=420
l=420:10
l=42
L=4*42
l=168
L=4l
P= 2(L + l)
420= 2(4l + l)
420=2 x 5l
420=10l rezulta ca l=42
deci L=4x42= 168.
P= 2(L + l)
420= 2(4l + l)
420=2 x 5l
420=10l rezulta ca l=42
deci L=4x42= 168.