Question

he regular nonagon has rotational symmetry of which angle measures? Check all that apply. 40° 45° 120° 240° 260° 320°

Answer 1

40 240 and 320 is the correct answers

Answer 2

Answer: An nonagon is a regular shape of 9 sides with the same length.

As this has 9 sides, then the angle of rotational symmetry will be n*2π/9

where n is an integer.

writing it in degrees, the angles will have the for of n*360°/9

so the angles are:

n = 0 ------------- a = 0°

n = 1 -------------- a = 40°

n= 2 --------------- a = 80°

n= 3 --------------- a = 120°

..

and so on, adding by 40° each time.

so the answers are in the options that you give are 40°, 120°, 240°, 260° and 320°.