Regular decagon ABCDEFGHIJ rotates 360 counterclockwise about it's center. At which angle of rotation does A' (the image of A) coincide with D?

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Question

Regular decagon ABCDEFGHIJ rotates 360 counterclockwise about it's center. At which angle of rotation does A' (the image of A) coincide with D?

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anonymous · Answer

its a regular  decagon
so each triangle from origin will make 36* angle

anonymous · Answer

now clockwise D is 7 units away
so 7*36 will be your answer

anonymous · Answer

252 degree angle rotation :)

anonymous · Answer

Thank u for helping me appreciate it

anonymous · Answer

Do you mind helping me with another question?

anonymous · Answer

alright

anonymous · Answer

A regular octagon rotates 360° about its center. How many times does the image of the octagon coincide with the preimage during the rotation?

A. 1
B. 2.
C.4
D.8

anonymous · Answer

after 360* rotation it will come back to its original position
so just one
its A

anonymous · Answer

thanks

anonymous · Answer

welcome (:

anonymous · Answer

252 is wrong