4. Proving Triangles Congruent-ASA, AAS
Sign In
Statements
|
Reasons
|
1. ∠ 2 ≅ ∠ 1 and ∠ 1 ≅ ∠ 3
|
1. Given
|
2. ∠ 2 ≅ ∠ 3
|
2. Transitive Property of Congruence
|
3. ∠ 2 and ∠ 3 are alternate interior angles
|
3. From the diagram
|
4. AB ∥ DE
|
4. Converse of Alternate Interior Angles Theorem
|
Since ∠ 2 ≅ ∠ 1 and ∠ 1 ≅ ∠ 3, by the Transitive Property of Congruence we get ∠ 2 ≅ ∠ 3. Next, by the Converse of Alternate Interior Angles Theorem we conclude that AB ∥ DE. We summarize this proof in the following table.
Statements
|
Reasons
|
1. ∠ 2 ≅ ∠ 1 and ∠ 1 ≅ ∠ 3
|
1. Given
|
2. ∠ 2 ≅ ∠ 3
|
2. Transitive Property of Congruence
|
3. ∠ 2 and ∠ 3 are alternate interior angles
|
3. From the diagram
|
4. AB ∥ DE
|
4. Converse of Alternate Interior Angles Theorem
|