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AEA CONJECTURE

AEA Conjecture

Definition Of AEA (Alternate Exterior Angle) Conjecture

AEA (Alternate Exterior Angle) Conjecture states that if two parallel lines are cut by a transversal, then the alternate exterior angles are congruent.

More About AEA Conjecture

Two pairs of alternate exterior angles are formed when two parallel lines are cut by a transversal

Examples of AEA Conjecture

example of AEA Conjecture

Here a and b are two parallel lines and c is the transversal.∠2, ∠7 and ∠3, ∠6 are pairs of alternate exterior angles. According to AEA (alternate exterior angle) conjecture ∠2 and ∠7 are congruent, and ∠3 and ∠6 are congruent and can be represented as ∠2≅∠7 and∠3≅∠6.

Video Examples: Alternate Exterior Angle Theorem

 

Solved Example on AEA Conjecture

Ques: 
The lines l and m are parallel in the figure. Which of the angles satisfies the AEA conjecture?

example of AEA Conjecture

Choices:

A. ∠5 and ∠6
B. ∠1 and ∠6
C. ∠3 and ∠8
D. ∠1 and ∠4

Correct Answer: B

Solution:

Step 1: Only alternate exterior angles of parallel lines satisfy the AEA conjecture.
Step 2: Angles formed on the outside of two parallel lines and on the opposite of transversal are called alternate exterior angles of the parallel lines.
Step 3: The alternate exterior angles of the figure are ∠1 and ∠6, ∠2 and ∠7.
Step 4: Here, ∠1 and ∠6 are alternate exterior angles and hence congruent to each other.
Step 5: So, ∠1 and ∠6 satisfy the AEA conjecture.

Quick Summary

  • Alternate exterior angles are formed on the outside of two lines and on opposite sides of the transversal.
  • If the lines are parallel, alternate exterior angles are congruent.
\[ \text{If } l \parallel m \text{ and } t \text{ is a transversal, then } \angle 2 \cong \angle 7 \text{ and } \angle 3 \cong \angle 6 \text{ (referring to the provided diagram)} \]

🍎 Teacher Insights

Use visual aids and hands-on activities to help students distinguish between different types of angles formed by transversals.

🎓 Prerequisites

  • Parallel lines
  • Transversals
  • Angles
  • Congruence

Check Your Knowledge

Q1: If two parallel lines are cut by a transversal, and one alternate exterior angle measures 60 degrees, what is the measure of the other alternate exterior angle?

Q2: Lines 'a' and 'b' are cut by transversal 't'. Angle 1 and Angle 8 are alternate exterior angles. If Angle 1 = 100 degrees and Angle 8 = 80 degrees, are lines 'a' and 'b' parallel?

Frequently Asked Questions

Q: What are alternate exterior angles?
A: Alternate exterior angles are pairs of angles that lie on the outside of two lines and on opposite sides of a transversal.

Q: When are alternate exterior angles congruent?
A: Alternate exterior angles are congruent if and only if the two lines cut by the transversal are parallel.

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