Triangle Proofs

Front

What are Alternate Interior Angles?

Back

Angles that are on opposite sides of a transversal and inside the two lines it intersects. They are congruent when the lines are parallel.

Front

What is the Angle Bisector?

Back

A line that divides an angle into two equal parts.

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 first statement in the reason column of a proof?

Back

Given.

Front

What does SSS stand for in triangle congruence?

Back

Side-Side-Side; a criterion for triangle congruence stating that if three sides of one triangle are equal to three sides of another triangle, the triangles are congruent.

Front

What does SAS stand for in triangle congruence?

Back

Side-Angle-Side; a criterion for triangle congruence stating that if two sides and the included angle of one triangle are equal to two sides and the included angle of another triangle, the triangles are congruent.

Front

What does AAS stand for in triangle congruence?

Back

Angle-Angle-Side; a criterion for triangle congruence stating that 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, the triangles are congruent.

Front

What is the definition of SAA?

Back

Side-Angle-Angle; a criterion for triangle congruence that is not valid.

Front

What is the definition of SSA?

Back

Side-Side-Angle; a criterion for triangle congruence that does not guarantee congruence.

Front

What is the purpose of a proof in geometry?

Back

To provide a logical argument that demonstrates the truth of a geometric statement.