60
the interior angle measure of a regular polygon is calculated with the following formula, where n represents the number of sides or interior angles of the regular polygon.
interior angle = 180 (n-2)/n
a. determine the measure of the interior angles of a regular decagon. in your answer, include all calculations.
b. use your result from part a to identify whether or not a regular decagon can be used as the only shape in a regular tessellation.

A 144

B no

Step-by-step explanation:

Decagon is a 10 sided figure

interior angle = 180 (n-2)/n where n=10

                         180*(10-2)/10

                           180*8/10

                           144

To tessellate, the angle must divide evenly into 360

360/144= 2.5

This is not evenly so it will not tessellate

144

no

Step-by-step explanation:

366

step-by-step explanation:

given that triangle abc is transformed two times to get triangle

a"b"c"

first abc is transformed in to a'b'c' as follows:

the coordinates of a are (1,-1) and transformed into a'(-1,1)

similarly b (4,-2) became b'(-4,2) and

c(7,-2) became c'(-7,2)

i.e. (x,y) becomes (-x,-y)

this is nothing but reflection about a point here origin.

thus first transformation is reflection on the origin.

next is exactly shifting 3 units down

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