Triangle Congruence: SSS and SAS Methods

This video tutorial by Mrs. Whiting covers triangle congruence using the Side-Side-Side (SSS) and Side-Angle-Side (SAS) postulates. It explains how to prove triangles congruent without verifying all angles and sides, introduces the concept of included angles, and provides practice problems. The tutorial also includes detailed proofs using these postulates, emphasizing the importance of matching corresponding parts and using properties like reflexive and vertical angles.

What is the main purpose of the SSS postulate?

• To prove that two triangles are similar

• To prove that all sides in a triangle are equal

• To prove that all angles in a triangle are equal

• To prove that two triangles are congruent by comparing all three sides

In the SSS postulate, which of the following must be true?

• One side and one angle of one triangle must be equal to one side and one angle of another triangle

• Two sides and the included angle of one triangle must be equal to two sides and the included angle of another triangle

• All three sides of one triangle must be equal to all three sides of another triangle

• All three angles of one triangle must be equal to all three angles of another triangle

What is an included angle?

• An angle that is not between two sides

• An angle that is between two sides

• An angle that is equal to 90 degrees

• An angle that is equal to 180 degrees

Which postulate requires the included angle to be known?

• SAS

• ASA

• AAS

• SSS

In the SAS postulate, what must be true about the angle?

• It must be the largest angle in the triangle

• It must be the included angle between the two sides

• It must be the smallest angle in the triangle

• It must be an exterior angle

What is the reflexive property of congruence?

• Any side is equal to itself

• Any two sides are equal

• Any angle is equal to itself

• Any triangle is equal to itself

Which postulate would you use if you have two pairs of sides and the included angle congruent?

• SSS

• ASA

• SAS

• AAS

What is the final reason in a proof if you have three pairs of congruent sides?

• ASA

• SSS

• AAS

• SAS

In a proof, what should you check if you are using the SSS postulate?

• Three pairs of congruent sides

• Two pairs of congruent sides and one pair of congruent angles

• One pair of congruent sides and two pairs of congruent angles

• Three pairs of congruent angles

What does the definition of perpendicular lines state?

• They form straight angles

• They form right angles

• They form acute angles

• They form obtuse angles