Zadanie
x - bok kwadratu
a = x + 3 - jeden bok prostokąta
b = x - 1 - drugi bok prostokąta
Ob. = 2a + 2b
2(x + 3) + 2(x - 1) = 32
2x + 6 + 2x - 2 = 32
4x + 4 = 32 l -4
4x = 28 l :4
x = 7 cm - bok kwadratu
a = x + 3 = 7 + 3 = 10 cm
b = x - 1 = 7 - 1 = 6 cm
Pole kwadratu
P = x²
P = 7² = 49 cm²
Pole prostokąta
P = a · b
P = 10 · 6 = 60 cm²