Odpowiedzi

2010-01-18T18:51:06+01:00
A)
Pc = 2ab + 2ac + 2bc
a = 30 cm
b = 3dm = 30 cm
c = 50 cm


Pc = 2 * 30cm * 30cm + 2 * 30cm * 50cm + 2 * 30cm * 50 cm = 2 * 900 cm + 2 * 1500 cm + 2 * 1500 cm = 1800 cm + 3000 cm + 3000cm = 7800 cm < kwadratowych >

b)
Pc = 2ab + 2ac + 2bc
a = 0,2 m = 20 cm
b = 40 cm
c = 5 dm = 50 cm

Pc = 2 * 20 cm * 40 cm + 2 * 20 cm * 50 cm + 2 * 50 cm * 40 cm = 2 * 900 cm + 2 * 1000 cm + 2 * 2000 cm = 1800 cm + 2000 cm + 4000 cm = 7600 cm <kwadratowych>