Odpowiedzi

2010-04-11T19:20:15+02:00
R=⅓ h
3=⅓ h
h= 9
h= a√3 / 3
a√3 / 3 = 9
a= 27/ √3 = 27√3/ 3 =9√3
P= a²√3 / 4
P= (9√3)²√3 / 4= 243√3 / 4


2010-04-11T19:24:26+02:00
R = 3cm
r = 2/3h (h - wysokość tr. równobocznego)
r = 1/3a√3 (zależnoć między bokiem a promieniem)
1/3a√3 = 3 |*3
a√3 = 9 |:√3
a = 9/√3
a = 9√3/3 = 3√3
P = a²√3/4
P = (3√3)²√3/4
P = 27√3/4 cm²

2010-04-11T19:31:34+02:00
R= 3
h = 2/3 r
h= 2/3 * 3
h= 2

^ - do kwadratu
x^ = (1/2)^ + 2^
x^ = 1/4 + 4
3/4 x = 4 |: 3/4
x= 16/3

P = 1/2 ah
P = 2 * 16/3 * 1/2
p= 16/3
p= 5 i 1/3