Odpowiedzi

2015-12-01T17:20:15+01:00
A) Podstawa a = 10cm
 podstawa b = 4cm
ramiona - 5cm
5 cm= √[0.5 *(10cm-4cm)]²+h²
25 cm= (3cm) +h²
h² = 25cm-9cm
h² = 16cm
h= √16cm
h = 4 cm
Pole trapezu = (4cm+10cm) : 2 * 4cm = 14cm² * 2 = 28cm²

b)
a = 7cm
d1 = 10cm

a²=0.5d1² + (0.5d2)²
7² = 5² +(0.5d2)²
49 = 25 + (0.5d2)²
(0.5d2)² = 49-25
(0.5d2)² = 24
0,5d2 = 2√6
d2 = 4√6

Pole rombu = 4√6cm * 10cm :2 = 20√6cm²
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