Question

The area of a circle is 615.44 in^2. What is the diameter of the circle? Use 3.14 for π.

Answer 1

@Michele_Laino

Answer 2

we can apply this formula:
\[\huge A = \frac{{\pi {d^2}}}{4}\]
where \(A\) is the area, and \(d\) is the diameter

Answer 3

If we write the inverse formula, we get:
\[\huge d = \sqrt {\frac{{4A}}{\pi }} \]

Answer 4

is the answer 14 in

Answer 5

or:
\[\huge d = \sqrt {\frac{{4A}}{\pi }} = \sqrt {\frac{{4A}}{{3.14}}} \]

Answer 6

I got a different value

Answer 7

mmm let me see

Answer 8

20 in

Answer 9

hint:
here is the next step:
\[\huge \begin{gathered}
d = \sqrt {\frac{{4A}}{\pi }} = \sqrt {\frac{{4A}}{{3.14}}} = \hfill \\
\hfill \\
= \sqrt {\frac{{4 \times 615.44}}{{3.14}}} = \sqrt {\frac{{2461.76}}{{3.14}}} = ...? \hfill \\
\end{gathered} \]

Answer 10

ok is it 28

Answer 11

that's right!

Answer 12

thanks

Answer 13

:)