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2 years ago

The area of a circle is 80.86cm2. Find the length of the radius rounded to 2 DP.

Mathematics

1 answer:

weeeeeb [17]2 years ago

5 0

Answer:

Solution given:

The area of a circle =80.86cm²

we have:

The area of a circle =πr²

substituting value of area of circle we get

80.86cm=3.14*r²

dividing both side by 3.14

80.86/3.14=3.14*r²/3.14

25.75=r²

doing square root on both side

$\sqrt{25.75}=\sqrt{r²}$

r=5.07cm

The length of radius is 5.07cm

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From the question we are told that

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