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**cooljackiec****Member**- Registered: 2012-12-13
- Posts: 185

OPQRSTUVWX is a regular decagon. A rotation of

degrees about U maps X to R. Given , findTwo lines

and m intersect at O at an angle of . Let A be a point inside the acute angle formed by and m. Let B and C be the reflections of A in lines and m, respectively. Find the number of degrees in .Equilateral triangle ABC has centroid G. Triangle A'B'C' is the image of triangle ABC upon a dilation with center G and scale factor -2/3. Let K be the area of the region that is within both triangles. Find K/[ABC].

I see you have graph paper.

You must be plotting something

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**cooljackiec****Member**- Registered: 2012-12-13
- Posts: 185

are there any hints or solutions here??

I see you have graph paper.

You must be plotting something

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**anonimnystefy****Real Member**- From: Harlan's World
- Registered: 2011-05-23
- Posts: 16,037

72 degrees is the answer for the first one.

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