Question

What's the formula for R in C= 2•3.14r

Answer 1

$C=2\cdot3.14r\\\\C=6.28r\\\\6.28r=C\ \ \ \ |divide\ both\ sides\ by\ 6.28\\\\\huge\boxed{r=\dfrac{C}{6.28}}$


$C=2\pi r\\\\2\pi r=C\ \ \ \ |divide\ both\ sides\ by\ 2\pi\\\\\huge\boxed{r=\frac{C}{2\pi}}$