1. Prove Triangles Congruent by SAS
4.9
Prove Triangles Congruent by SAS
Side-Angle-Side (SAS) Congruence Postulate
If two sides and the included angle of one triangle are congruent to two sides and the included angle of a second triangle, then the two triangles are congruent. S R T V U W

2. Prove Triangles Congruent by SAS
4.9
Prove Triangles Congruent by SAS
Example 1
Use the SAS Congruence Postulate M N L R S T
Solution
It is given that
and __________.
SAS Congruence Postulate
So, by the ____________________________,

3. Prove Triangles Congruent by SAS
4.9
Prove Triangles Congruent by SAS
Hypotenuse-Leg Congruence Theorem
If the hypotenuse and a leg of a right triangle are congruent to the hypotenuse and a leg of a second right triangle, then the two triangles are ___________. B A C E D F
congruent

4. Prove Triangles Congruent by SAS
4.9
Prove Triangles Congruent by SAS
Example 2
Use the HL Congruence Theorem B A C D E
Write a proof.
Given:
Prove:
Statements
Reasons
Given
Given

5. Prove Triangles Congruent by SAS
4.9
Prove Triangles Congruent by SAS
Example 2
Use the HL Congruence Theorem B A C D E
Write a proof.
Given:
Prove:
Statements
Reasons
right angles
right
right triangles
triangle

6. Prove Triangles Congruent by SAS
4.9
Prove Triangles Congruent by SAS
Example 2
Use the HL Congruence Theorem B A C D E
Write a proof.
Given:
Prove:
Statements
Reasons
Given
HL Congruence Theorem

7. Prove Triangles Congruent by SAS
4.9
Prove Triangles Congruent by SAS
Checkpoint. Complete the following exercises.
Decide whether enough information is given to prove ABC LMN using the SAS Congruence Postulate. A B C
Sides: N M L
Included angle:
Therefore there is enough information

8. Prove Triangles Congruent by SAS
4.9
Prove Triangles Congruent by SAS
Checkpoint. Complete the following exercises. P S Q R
Write a proof.
Given:
Prove:
Statements
Reasons
Given
Given
Definition of perp. lines
Definition of a right triangle

9. Prove Triangles Congruent by SAS
4.9
Prove Triangles Congruent by SAS
Checkpoint. Complete the following exercises. P S Q R
Write a proof.
Given:
Prove:
Statements
Reasons
Reflexive Property of Cong.
HL Congruence Theorem

10. Prove Triangles Congruent by SAS
4.9
Prove Triangles Congruent by SAS
Pg. 262, 4.9 #1-16