The point in a triangle at which the medians of a triangle intersect.
The point at which the perpendicular bisectors
of a triangle intersect.
Intersecting at one point; lines, rays, segments, etc. are concurrent when they
intersect at one point.
The segment contained by a secant segment with an endpoint on the circle and
at the fixed point outside the circle whose points all lie outside the circle
(except the endpoint on the circle).
The point in a triangle at which the angle
bisectors of a triangle intersect. This point
is also the center of a circle inscribed in the triangle.
An angle whose vertex lies on a circle and whose sides are contained by secant
The segment contained by a secant segment whose endpoints are both on the
A trapezoid with congruent legs.
Lower Base Angles
The angles in an isosceles trapezoid whose vertices are the endpoints of the
Median of a Triangle
A segment within a triangle with one endpoint at a vertex of the triangle and
the other endpoint at the midpoint of the side opposite the vertex. Every
triangle has three medians.
A segment within a triangle whose endpoints are midpoints of the sides of the
triangle. Every triangle has three midsegments.
The point at which the altitudes of a triangle
Point of Concurrency
The intersection point of concurrent lines, segments, etc.
Remote Interior Angles
The two angles of a triangle that are not adjacent to the exterior angle which
is drawn by extending one of the sides.
A segment with one endpoint on a circle, the other endpoint at a fixed point
outside the circle, and one point of intersection with the circle, not including
A statement about geometric figures that has been proved in the past, and can be
accepted as a truth in the present without proof. A list of important theorem's
can be found in review
Upper Base Angles
The two angles of an isosceles trapezoid whose vertices are the endpoints of
the smaller base.