z.1
Mamy
c2 = 82 + x2 = 64 + x2
2*4 + 2 x = 2 c / : 2
c = 4 + x
zatem
( 4 + x)2 = 64 + x2
16 + 8 x + x2 = 64 + x2
8 x = 48
x = 6
====
c2 = 82 + 62 = 64 + 36 = 100
c = 10
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Pole trapezu
P = 0,5 *(a + b)*h = 0,5*( 16 + 4)*8 = 4*20 = 80
====================================
h=2r=8 , r2=2*a ⇒ a=8
| 2a+b | ||
P= | *h = ............ = 80 | |
| 2 |
| 11+15 | ||
h= 5,5+7,7=13 , P= | *13=....... | |
| 2 |
| a+b | ||
zad2/ h= | ||
| 2 |
| a+b | ||
P= ( | )2= 132=169 | |
| 2 |