Use the arc length formula: (s = rtheta) when (theta) is in radians
Use the arc length formula: (s = frac{theta}{360^circ} cdot 2pi r) when (theta) is in degrees
Identify the radius (r)
Identify the central angle (theta)
Convert the angle to radians if using (s = rtheta)
Substitute the values into the correct formula
Compute the result
Check that the units are in linear units, such as cm, m, or in