Sides of a polygon that share a vertex.
One of the parallel sides of a trapezoid.
Center of a Regular Polygon
The point on the interior of a polygon
from which all vertices of the polygon are equidistant.
A curve whose starting point is the same as its ending point.
A polygon with one or more interior angles greater than 180
Polygons whose sides are all congruent
Vertices of a polygon that include the endpoints of the same side.
Without any gaps or holes.
A polygon whose interior angles are all less than 180 degrees.
Angles in a polygon that share a
segment as one of the sides that could be
extended into a ray.
An arrangement of continuous points in
A ten-sided polygon.
A line segment joining nonconsecutive
vertices of a polygon.
A twelve-sided polygon.
A polygon whose angles are
A polygon whose sides are congruent.
The angle formed at a vertex of a polygon
that lies outside of the region enclosed by a polygon.
A seven-sided polygon.
A six-sided polygon.
The angle formed, at a vertex of a
polygon, that lies inside the region enclosed by the polygon.
One of the nonparallel sides of a trapezoid.
The segment in a trapezoid whose
endpoints are the midpoints of the legs of
A nine-sided polygon.
Sides of a quadrilateral that don't share a vertex.
An eight-sided polygon.
A quadrilateral with two pairs of parallel
A five-sided polygon.
A simple closed curve consisting of the union of
segments that intersect each other at their
A four-sided polygon.
A quadrilateral with four congruent
An equilateral, equiangular polygon.
A quadrilateral with four congruent sides.
One segment that comprises part of a polygon.
Simple Closed Curve
A closed curve that does not intersect itself.
A quadrilateral with four congruent sides
A quadrilateral with one pair of parallel
A three-sided polygon.
The common endpoint of two sides of a polygon.
A polygon with n sides has n(n-3)/2 diagonals.
Interior Angle Sum
The interior angle sum of a polygon with n sides is 180(n-2) degrees.