If you wish to communicate information, I suggest you call it an 180-gon. Although there is a prefix for 180 I suggest you keep it simple. Not only is the use of long Greek prefices pretentious, you will only annoy the reader who will probably have to consult a dictionary. Having said that, if you do want to be pretentious or obfuscate, you can use the link below for polygons with up to 999 sides. http://faculty.kutztown.edu/schaeffe/Tutorials/General/Polygons.html
a 4 sided shape is called a quadrilateral
180
always 180.
There is no three-sided shape with two obtuse angles, because the three interior angles of a three-sided shape, which is a triangle, add up to 180 degrees, and two obtuse angles would be over 180 degrees.
== == A 56 sided shape is called a Pentacontakaihexagon.
The internal angles of an n-sided shape add to (n-2)*180 degrees. So, for an 8-sided shape, they would add to 6*180 = 1080 degrees.
540 degrees total degrees in shape = (( 180 x number of sides of shape) - 360)
it is called a seven sided shape in Canada
a one sided shape is called a henagon and a 2 sided shape is called a digon
A 10-sided shape is called a decagon.
An five sided shape is called a Pentagon
a 69 sided shape is called a sexagon
A 90 sided shape is called Enneacontagon.
A 35 sided shape is called a triacontakaipentagon
A 150 sided shape is called heptaconta.
Hommasquabblelagagon
The 22 sided shape is called a: ICOSIKAIDIGON