Suppose that you needed to make a pen for some small animals. You have 12.0 m of fencing. You decide to make a circular pen, because if you wish to enclose an area using a given length of fencing, then a circular fence encloses a larger area than a fence of any other shape. What is the area A of the pen

Respuesta :

Answer:

[tex]A = 11.465\ m^2[/tex]

Step-by-step explanation:

Given

[tex]Fencing = 12\ m[/tex]

Required

Determine the area of the pen

The given parameter represents the perimeter of the pen;

Since, the pen is circular, we have circumference, C:

[tex]C = 2\pi r[/tex]

Substitute 12 for C

[tex]12 = 2\pi r[/tex]

Divide through by 2

[tex]6 = \pi r[/tex]

Make r the subject of formula

[tex]r = \frac{6}{\pi}[/tex]

The area (A) of the pen is calculated as follows;

[tex]A = \pi * r^2[/tex]

Substitute [tex]\frac{6}{\pi}[/tex] for r

[tex]A = \pi * (\frac{6}{\pi})^2[/tex]

Open Bracket

[tex]A = \pi * \frac{36}{\pi^2}[/tex]

[tex]A = \frac{36}{\pi}[/tex]

Take [tex]\pi[/tex] as 3.14

[tex]A = \frac{36}{3.14}[/tex]

[tex]A = 11.465\ m^2[/tex] (Approximated)