Odpowiedzi

2009-12-10T16:59:02+01:00
2dm=10cm.
12cm*3=36cm
P= 12cm+36cm*10cm:2= 48cm*10:2=480cm:2= 240cm2
P= 240cm2
2009-12-10T17:00:56+01:00
Dane;
h=2dm = 20cm
a=12cm
b=3xa
b= 3 * 12cm= 36cm
P= (a+b) *h
-----------
2
P= (12+36) *20
-------------
2
P=⁴⁸ * ¹⁰ 480cm²
-------- =
1
odp . Pole tego trapezu wynosi 480cm².
2009-12-10T17:19:07+01:00
Wysokość- 2dm=20cm
podstawa górna= 12cm
podstawa dolna= 12 *3=36cm
wzór na pole- (a+b)*h :2
pole- (12+36)*20 :2=48*10=480cm²