Question

Find the area of a circle with a radius of 8. Either enter an exact answer in terms of pie or use 3.14 for pie and enter your answer as a decimal

Answer 1

The area is:

200.96 units²

Work/explanation:

The formula for the area of a circle is:

`\sf{A=\pi r^2}}`

Where

A = area

π = 3.14

r = radius

Diagram:

`\setlength{\unitlength}{1cm}\begin{picture}(0,0)\thicklines\qbezier(2.3,0)(2.121,2.121)(0,2.3)\qbezier(-2.3,0)(-2.121,2.121)(0,2.3)\qbezier(-2.3,0)(-2.121,-2.121)(0,-2.3)\qbezier(2.3,0)(2.121,-2.121)(-0,-2.3)\put(0,0){\line(1,0){2.3}}\put(0.5,0.3){\bf\large 8\ cm}\end{picture}`

Plug in the data:

`\large\begin{gathered}\bf{A=3.14*8^2}\\\bf{A=3.14*64}\\\bf{A=200.96\:units^2}\end{gathered}`

Hence, the area is 200.96 units²

Answer 2

64π

Explanation:

The area of a circle can be found using the formula:

A=πr^2

The radius is 8, so we can plug that into the equation.

A=π(8)^2

Simplify.

A=64π

Or, as a decimal:

A=64*3.14

A=200.96