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Find the area of a circle with diameter = 10.5in. please help me right now pleasee.

User Rich Steinmetz
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1 Answer

9 votes
9 votes

The area of a circle of radius r is given by the formula:


A=\pi\cdot r^2

On the other hand, the radius r is half the diameter D of the circle:


r=(D)/(2)

Substitute D=10.5 in to find the radius:


\begin{gathered} r=\frac{10.5\text{ in}}{2} \\ \therefore r=5.25\text{ in} \end{gathered}

Use the value r=5.25 in to find the area of the circle:


A=\pi\cdot(5.25in)^2

Use a calculator to find the numerical value of the expression. We get that:


A\approx86.59in^2

User Kassens
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