Odpowiedź :
Zadanie
a = 1 dm = 10 cm
b = 6 cm
c = 2 dm = 20 cm
P = 2ab + 2ac + 2bc
P = 2 · 10 · 6 + 2 · 10 · 20 + 2 · 6 · 20 = 120 + 400 + 240 = 760 cm² = 7,6 dm²
Zadanie
a = 1 dm = 10 cm
b = 6 cm
c = 2 dm = 20 cm
P = 2ab + 2ac + 2bc
P = 2 · 10 · 6 + 2 · 10 · 20 + 2 · 6 · 20 = 120 + 400 + 240 = 760 cm² = 7,6 dm²