Congruent Triangles

Front

What are congruent triangles?

Back

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

Front

What does it mean for angles to be congruent?

Back

Two angles are congruent if they have the same measure.

Front

State the Congruence Postulate: SSS (Side-Side-Side).

Back

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

Front

State the Congruence Postulate: SAS (Side-Angle-Side).

Back

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

Front

State the Congruence Postulate: ASA (Angle-Side-Angle).

Back

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

Front

State the Congruence Postulate: AAS (Angle-Angle-Side).

Back

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

Front

What is the relationship between corresponding angles in congruent triangles?

Back

All corresponding angles in congruent triangles are congruent.

Front

If ∆ABC ≅ ∆DEF, what can be said about the sides?

Back

The corresponding sides of ∆ABC and ∆DEF are equal in length.

Front

How do you find the measure of a missing angle in a triangle?

Back

Use the fact that the sum of the angles in a triangle is 180 degrees.

Front

If ∠A = 50° and ∠B = 60°, what is ∠C?

Back

∠C = 180° - (∠A + ∠B) = 180° - (50° + 60°) = 70°.