Question

Find the area of circle having 176cm circumference.With step by step explanation.plz​

Answer 1

`\huge\boxed{A=784\pi\ cm^2\approx2464\ cm^2}`

Explanation:

The formula of a circumference of a circle:

`C=2\pi r`

r - radius

The formula of an area of a circle:

`A=\pi r^2`

r - radius

We have C = 176cm. Substitute to the formula and calculate the radius r:

`2\pi r=176\qquad|\text{divide both sides by}\ 2\pi\\\\r=(176)/(2\pi)\\\\r=(88)/(\pi)\qquad|\text{use}\ \pi\approx(22)/(7)\\\\r=(88)/((22)/(7))\\\\r=88\cdot(7)/(22)\\\\r=4\cdot7\\\\\boxed{r=28(cm)}`

Calculate the area:

`A=\pi\cdot28^2=784\pi\approx784\cdot(22)/(7)=112\cdot22=2464(cm^2)`

According to the moderator, I should take
`\pi\approx3.14`. You can do it like that. In my opinion, my solution is correct.