# Triangle congruence

Question Answer
a line drawn in a figure to aid in a proof. Auxiliary Line
A triangle with three acute angles Acute Triangle
A triangle with three congruent acute angles Equiangular Triangle
A triangle with one right triangle Right Triangle
A triangle with one obtuse triangle Obtuse Triangle
A triangle with three congruent sides Equilateral Triangle
A triangle with at least two congruent sides Isosceles Triangle
A triangle with no congruent sides Scalene Triangle
A theorem whose proof follows directly form another theorem. Corollary
The set of all points inside a figure Interior
The set of all points outside a figure Exterior
An angle formed by two sides of a triangle Interior Angle
An angle formed by one side of the triangle and the extension of an adjacent side Exterior Angle
An interior angle that is not adjacent to the exterior angle Remote interior angle
Angels in the same position in two different polygons that have the same number of angles. Corresponding angles of polygons
Sides in the same position in two different polygons that have the same number of sides. Corresponding sides of polygons
Two polygons whose corresponding sides and angles are congruent. Congruent polygons
A property of triangles that states that if the side lengths of a triangle are fixed, the triangle can have only one shape. Triangle rigidity
An angle formed by two adjacent sides of a polygon. Included angle
The common side of two consecutive angles in a ploygon. Included side
CPCTC Corresponding Parts of Congruent Triangles are Congruent.
Congruent sides of an isosceles triangle Legs
The angle formed by the legs Vertex angle
The side opposite the vertex angle Base
The two angles that have the base as a side Base angles