Question

The area of a circle is found by the equation A=πr^2. If the area of a certain circle is 25π square inches, find it's radius r

Answer 1

• 5 inches.

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Given :

• The area of a circle is 25π sq.in

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To Find :

• The Radius.

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Solution :

We know,

`{ \longrightarrow\qquad \bf\pi {r}^(2) = \bf{Area_((Circle) ) }}`

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Where,

• r is the radius of the circle.

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Now, Substituting the values :

`{ \longrightarrow\qquad \sf\pi {r}^(2) = 25 \pi }`

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Cancelling π from both sides :

`{ \longrightarrow\qquad \sf \cancel\pi {r}^(2) = 25 \cancel\pi }`

`{ \longrightarrow\qquad \sf {r}^(2) = 25 }`

`{ \longrightarrow\qquad \sf {r}= √(25) }`

`{ \longrightarrow\qquad \pmb{\bf {r}= 5 }}`

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Therefore,

• The Radius of the circle is 5 inches .