Question

Mrs. Hellerud bought 18.84 feet of fencing to go around her tree in her front yard. She wants to know the area to find how big of a bag of mulch she needs to buy to fill the space between the tree and fence. What is the area?

Answer 1

the fencing is the perimeter to the tree, then we can use the formula of the perimeter of a circle to replace this value

`\begin{gathered} P=2*\pi* r \\ 18.84=2*\pi* r \end{gathered}`

now we can solve r from the formula to know the radious

`(18.84)/(2*\pi)=r`

we can use 3.14 to pi

`\begin{gathered} r=(18.84)/(2*3.14) \\ \\ r=3 \end{gathered}`

the value of the radio is 3 feet

now we can use the formula of the area of the circle to calculate the total area

`A=\pi* r^2`

and replace the known value of the radious and pi

`\begin{gathered} A=3.14*3^2 \\ \\ A=28.26 \end{gathered}`

the area is 28.26 square feet