Răspuns :
(l+70)*4=4l+280....=>P*2=280*2....=>4l=280cm....=>l=280:4...=>l=70cm
(70+70+70+70)*2=P*2....=>P=2*(70+70)
P=2*140
P=280cm.........=> P*2=280*2....=>P*2=560cm
=>l=70cm
P=280cm
(70+70+70+70)*2=P*2....=>P=2*(70+70)
P=2*140
P=280cm.........=> P*2=280*2....=>P*2=560cm
=>l=70cm
P=280cm