A circle with a diameter of 18 cm is subdivided by a central angle of 60 degrees. What is the length of the subtended arc?

Question

How to find the length of the subtended by this angle

Answer 1

L=(q/360)∏(r) where q=60º and r=18/2=9

L=(60/180)∏(9)

L=(60/20)∏

L=3*∏

L=3*3.14159

L=9.42477 cm

also, 60º is 1/6 the distance (circumference) around the circle

C=∏d

C=3.14159*18

C=3.14159*18

C=56.54862

56.54862/6=9.42477 cm

Answer 2

Since this is geometry and involves a figure, the natural way to begin is to DRAW THE FIGURE and label its radius (half of its given diameter).

 

The sixty degree central angle subtends one sixth of the Circumference, i.e. one sixth of C, where C = 2(pi)(r).

 

Can you complete the task?