Vertex angle, vertex of an angle
Vertex angle the angle that is formed by two lines crossing at a vertex.
An angle associated with a vertex of a polygon.
A vertex angle is measured in degrees.
Vertex angles of regular polygons
Angle formulas for regular polygons
n – the number of sides
Vertex angle of an isosceles triangle
In an isosceles triangle, the apex is the vertex where the two sides of equal length meet, opposite the unequal third side.
The angles at the base are called the base angles, and the angle opposite the base is called the vertex angle.
