Question

a photograph of a full moon is enlarged so that the diameter is 8 times larger. how much larger is the circumfrence?​

Answer 1

25.13

Explanation:

Since the Diameter is 8 the equation to find the Circumference is pi time D

3.14 x 8 equals 25.13274...

Answer 2

let's recall that the radius of a circle is half of the diameter, now, if the diameter say "d" got enlarged 8 times, to it became 8d, then the radius "r" got enlarged 8 times as well, namely 8r.

`\bf \textit{circumference of a circle}\\\\ C=2\pi r~~ \begin{cases} r=radius\\ \cline{1-1} r=8r \end{cases}\implies \stackrel{\textit{is 8 times larger than that of the original}}{C=2\pi (8r)\implies C=\stackrel{\downarrow }{8}[2\pi r]}`