Math Is Fun Forum

cooljackiec

Member

Registered: 2012-12-13

Posts: 186

transformations

OPQRSTUVWX is a regular decagon. A rotation of

degrees about U maps X to R. Given

, find

Two 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].

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I see you have graph paper.
You must be plotting something

cooljackiec

Member

Registered: 2012-12-13

Posts: 186

Re: transformations

are there any hints or solutions here??

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I see you have graph paper.
You must be plotting something

anonimnystefy

Real Member

From: Harlan's World

Registered: 2011-05-23

Posts: 16,049

Re: transformations

72 degrees is the answer for the first one.

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