Triangle Proofs

Front

What is the definition of congruent triangles?

Back

Triangles that have the same size and shape, meaning their corresponding sides and angles are equal.

Front

What does the Side-Angle-Side (SAS) postulate state?

Back

If two sides and the included angle of one triangle are congruent to two sides and the included angle of another triangle, then the triangles are congruent.

Front

What is the Angle-Side-Angle (ASA) postulate?

Back

If two angles and the included side of one triangle are congruent to two angles and the included side of another triangle, then the triangles are congruent.

Front

What is the Side-Side-Side (SSS) postulate?

Back

If all three sides of one triangle are congruent to all three sides of another triangle, then the triangles are congruent.

Front

What is the Angle-Angle-Side (AAS) theorem?

Back

If two angles and a non-included side of one triangle are congruent to two angles and the corresponding non-included side of another triangle, then the triangles are congruent.

Front

What is the definition of a transversal?

Back

A line that intersects two or more lines at different points.

Front

What are corresponding angles?

Back

Angles that are in the same position on two parallel lines cut by a transversal.

Front

What is the definition of vertical angles?

Back

Angles that are opposite each other when two lines intersect; they are always congruent.

Front

What is the definition of an isosceles triangle?

Back

A triangle with at least two sides of equal length.

Front

What is the definition of an equilateral triangle?

Back

A triangle in which all three sides are of equal length and all three angles are equal.