In geometry, an interior angle is an angle formed by two sides of a simple polygon that share an endpoint, namely, the angle of the inner side of the polygon.
the two sides of a polygon meet at the angle
A point that two sides of a polygon have in common is called a vertex. Each regular polygon has an equal number of sides as vertices.
I am the endpoint where two sides of a polygon meet?
Polygon
either an obtuse, acute, or right angle
Any polygon can have, and every regular polygon has.
They form a vertex.
a vertex
Any polygon with 5 or more sides can have that. Also, a square, rhombus, kite or arrowhead.
A angle formed inside a polygon by two adjacent sides.
Interior Angle
The interior angle of a polygon is the angle formed by two adjacent sides of a polygon where the angle lies inside the area formed by the polygon. The exterior angle is that formed by one of these sides and the line formed by extending the other side. Consequently, External angle = 180 deg - Internal angle. Because they form supplementary angles, it does not matter which of the two sides you extend.
It is the number of sides of the polygon minus two as for example a pentagon has 5 sides and so 5-2 = 3 triangles
This is known in geometry as an interior angle.
Every polygon has two of its sides intersect.
The interior angle is the angle formed from two sides of a nth-sided polygon. Because the polygon is regular, all angles formed from any two sides of the polygon are equal. It can be proven, but I won't attempt to, that to find the amount of sides, you use 180-[interior angle], and divide the answer by 360. In this case, 180-156=24, 360/24= 15, thus the polygon has 15 sides. One way to prove it is to imagine the polygon and divide it into isosceles triangles. But I won't go there.