Obwód prostokąta = 2a + 2b
b = a - 35% = 100%*a - 35%*a = 65%*a = 0,65a
2a+2*0,65a=132
2a+1,3a=132
3,3a=132
a=40[cm]
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b=0,65a=0,65*40=26[cm]
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Pole prostokąta:
P=a*b=40*26=1040[cm^2]
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zadanie 2.
d = 12 cm
f = 12cm - 33,3%*12=12-0,333 *12 = 12 - 3,996 = 8,004
P=\frac{1}{2}df
a bok rombu
a^2=(\frac{1}{2}d)^2+(\frac{1}{2}f)^2=6^2+4,002^2=36+16,016004\approx52,026
a=\sqrt{52,02}\approx7,21
Ob=4*7,21=28,84