Question

derive the formula for the circumference of a circle with radius r by following these steps. smaller circle? c1 = π 3. suppose the radius of the larger circle is r. what is its diameter? d2 = 2r 4. if d2 = 2r, then the similarity equation in step 1 becomes (\frac{pi}{1}=\frac{c2}{2r}). solve this equation for c2. c2 =

Explanation:

Step1: Cross - multiply the equation

Given $\frac{\pi}{1}=\frac{C_{2}}{2r}$, cross - multiplying gives $\pi\times(2r)=1\times C_{2}$.

Step2: Simplify the expression

$C_{2} = 2\pi r$.

Answer:

$2\pi r$