Download 5 and 1 ∠ ∠ 6 and 2 ∠ ∠ 7 and 3 ∠ ∠ 8 and 4 ∠ ∠ 3 and 1

Parallel Lines Cut By a Transversal
Module 3*
Parallel
– Lines (on the same plane) that do not intersect
– Lines on a graph that have the same slope
n
l
l || m (l ine l i s parall el to l ine m)
1 2
4 3
m
5 6
8 7
transversal
Corresponding angles – Angles that are in the same position
Ex:
∠1 and ∠5
∠3 and ∠7
Theorem:
∠2 and ∠6
∠4 and ∠8
If parallel lines are cut by a transversal, then corresponding
angles are congruent.
Vertical Angles
Ex:
∠1 and ∠3
∠5 and ∠7
Theorem:
∠2 and ∠4
∠6 and ∠8
Vertical angles are congruent
Supplementary angles – Angles whose measures add to equal 180°
Linear Pair – Two adjacent angles the form a straight line
Interior of a Triangle – The sum of the interior angles of a triangle is equal to 180°
Alternate Interior/Exterior Angles
Interior
Ex:
∠3 and ∠5
Exterior
Ex:
∠1 and ∠7
∠4 and ∠6
∠2 and ∠8
Theorem:
If parallel lines are cut by a transversal, then Alternate
Interior/Exterior angles are congruent.