A closed geometric figure with the sum of internal angles equal to 180 degrees.

A closed geometric figure with equal diagonal length and congruent sides.

A dimensionless geometric figure.

A geometric figure formed from the intersection of two lines at only one distinct location.

A geometric figure that can be formed by at least two points.

A geometric figure that can be formed by the intersection of non-coinciding planes.

A geometric figure that can be formed by two non-coinciding lines.

The general term for the closed geometric figure with 4 sides.

A line segment joining a vertex to the midpoint of the opposite side, thus bisecting that side of a triangle.

The intersection of the three altitudes of a triangle.

Circles with common center.

A line that touches a circle at only one distinct points.

A chord in a circle that passes through the center.

The largest possible circle that can be drawn interior to a plane figure.

Graph of a quadratic function.