Zadanie 7
a)
a = 5,5 cm
b = 3 cm
H = 12 cm
Pb = 2·(a + b) · H
Pb = 2 · (5,5 + 3) · 12 = 24 · 8,5 = 204 cm²
b)
Ob. = 10 cm
H = 3,5 cm
Pb = Ob. · H
Pb = 10 · 3,5 = 35 cm²
c)
Ob. = 20 cm
H = 5 cm
Pc = 120 cm²
Pc = 2 · Pp + Pb = 2 · Pp + Ob. · H
2 · Pp + 20 · 5 = 120
2 · Pp + 100 = 120 l -100
2 · Pp = 20 l :2
Pp = 10 cm²
