Lin thinks that the central angle in circle A is congruent to the central angle in circle B. Do you agree with Lin?

Circumference of circle A:  C  =  2·pi·r   --->   C  =  2·pi·12  =  24pi

The portion of the circumference of 4pi is  4pi / 24pi    1/6

1/6^th of the circle would be 60^o.

 

Circumference of circle :  C  =  2·pi·r   --->   C  =  2·pi·3  =  6pi

The portion of the circumfBerence of pi is  pi / 6pi    1/6

1/6^th of the circle would be 60^o.

 

These central angles are congruent.