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## #1 2013-07-14 05:25:47

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

### 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].

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

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## #2 2013-07-16 04:47:06

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

### Re: transformations

are there any hints or solutions here??

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

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## #3 2013-07-16 05:47:41

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

### Re: transformations

72 degrees is the answer for the first one.

Here lies the reader who will never open this book. He is forever dead.
Taking a new step, uttering a new word, is what people fear most. ― Fyodor Dostoyevsky, Crime and Punishment
The knowledge of some things as a function of age is a delta function.

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