Respuesta :

the circumference of the circle when r=30 is C=60π
the arc is 18π, it is 18π/60π=3/10 of the whole circle
the arc is 3/10 of 360 degree, which is 108 degree
the central angle measures the same as the arc, 108 degree.

The measure of the central angle is 108 degrees.

What is central angle?

'A central angle is an angle whose vertex is the center O of a circle and the legs are radii intersecting the circle in two distinct points A and B.'

According to the given problem,

Circumference = π * d

                         = π * 2 * r

Fraction of circumference =  18 π  / (π*2*r)    (fraction of 360°)

Fraction of 360 degree circle = 360 *  18 π /( π *2 * r)

                                                 = 108°

Hence, we can conclude, the measure of central angle is 108°.

Learn more about central angle here: https://brainly.com/question/15284656

#SPJ2

Otras preguntas