Given: the theorem of the alternate exterior angles
We will prove the theorem as follows:
First, we will draw two parallel lines and a transversal
As shown, line 1 // Line 2
The angles (x) and (y) are alternate exterior angles
We will prove: m∠ x = m∠ y
The proof will be as follows:
Statements Reason
Line 1 // Line 2 Given
m∠ x = m∠ z The corresponding angles are congruent
m∠ y = m∠ z The vertical angles are congruent
m∠ x = m∠ y Transitive property of equality
