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2014-05-14T21:57:37+03:00
A)A=L·l
50 dm=5m
A=15·5=75 m²
b) l=2,5m
L=1,5m+l
L=1,5m+2,5m=4m
A=2,5m·4m=10m²
c)P=20dam=200m
l=L-20
P=2(L+l)⇒ 200m=2(L+L-20)
2(2L-20)=200
4L-40=200
4L=200+40
L=240/4=60m
l=L-20=60-20=40m
A=60m·40m=2400 m²
2014-05-14T22:08:44+03:00
A=L×l

a)l=50dm=5m
A=15×5=75m²
b)L=l+1,5=2,5+1,5=4m
A=4×2,5=10m²
c)P=40dam=400m
l=L-20=110-20=90m
P=2L+2l
400=2l+2(L-20)
400=2L+2L-40
440=4L
L=440÷4
L=110m
A=110×90=9900m²

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