A vertex (vertices for plural) is a point at which 2 or much more sides or edge of a geometric figure meet.

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Naming conventions for angles

The vertex of an edge is the usual endpoint of 2 rays that consist of the angle"s sides.


The vertex because that angle BAC, written ∠BAC, is allude A. The edge can also be called as ∠CAB or by just its vertex, ∠A. As soon as using 3 points to name the angle, constantly put the name of the peak in the middle. So, ∠BAC is no the same angle as ∠ABC or ∠BCA.

Be mindful when naming an angle the shares a common vertex with other angles.


∠BAC above cannot be named by just its vertex since angles ∠CAD and also ∠BAD both have A as their vertex. In this case each angle need to be named by the point out on every side making up the angle and also the angle"s vertex.

Naming conventions because that polygons

The endpoints of each side that a polygon room the vertices the the polygon. The vertices are likewise referred to together corners the the polygon.


Points A, B, C, and also D are vertices for the rectangle above. Polygons have the right to be called by their vertices as lengthy as lock are listed in consecutive order. The rectangle over can be called as ABCD, CBAD, or various other sequences, but not ACDB.

The vertices that a polygon are additionally the vertices that the interior angles that the polygon. The pentagon ABCDE below is one example.


Vertices of solids

In heavy geometry, a crest is the suggest where at the very least 3 edge meet.


One of the vertices of the five-sided polyhedron (pentahedron) over is shown. An alert that the 3 edges displayed meet in ~ the vertex. The pentahedron has a total of 6 vertices.

A square pyramid has 5 vertices.


In the pyramid above, A, B, C, D, and E room the vertices. Allude B is the highest allude in relationship to the base of the pyramid. This allude is recognized as the apex that the pyramid.

Circles and vertices

Circles carry out not have any kind of vertices. The main angle the a circle is the angle whose vertex is constantly the facility of the circle.


For the one with facility O above, ∠AOB is a central angle since its vertex, O, is likewise the facility of the circle.

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Vertices and also analytic geometry

In analysis geometry, the peak of the graph of a parabola is the graph"s maximum point or minimum point.