Solution:
Given a circle of center, A with radius, r (AB) = 6 units
Where, the area, A, of the shaded sector, ABC, is 9π
To find the length of the arc, firstly we will find the measure of the angle subtended by the sector.
To find the area, A, of a sector, the formula is
Substitute the values of the variables into the formula above to find the angle, θ, subtended by the sector.
To find the length of the arc, s, the formula is
Substitute the variables into the formula to find the length of an arc, s above
Hence, the length of the arc, s, is 3π units.