C= 2πr for r
what is the answer? i need solving this

Solving for r

divide 2 to both sides of the equation
C/2 = 2/2 pi * r
2/2=1

C/2 = pi * r

divide pi to both sides of the equation
C/(2 pi) = pi/pi *r
pi/pi=1

r= C/(2 pi)

not hard, just 2 steps or 1 if you divide by 2 pi at the same time

Here, C = 2πr

Divide both sides by 2π, 
so, C / 2π = 2πr/2π
r = C/2π

In short, Your Answer would be: C/2π

Hope this helps!