Răspuns :
P = 300 m l = L : 2 ⇒ L = 2l
P = 2L + 2l
P = 2 x 2l + 2l
300 = 4l + 2l
300 = 6 l
l = 300 : 6
l = 50
L = 2 x l = 2 x 50 = 100
L = 100 m
Verificare: P = 2L + 2l = 2 x 100 + 2 x 50 = 200 + 100 = 300 m
P = 2L + 2l
P = 2 x 2l + 2l
300 = 4l + 2l
300 = 6 l
l = 300 : 6
l = 50
L = 2 x l = 2 x 50 = 100
L = 100 m
Verificare: P = 2L + 2l = 2 x 100 + 2 x 50 = 200 + 100 = 300 m