2.6 Special Angles on Parallel Lines

2.6 Special Angles on Parallel Lines

Corresponding angles: Ð1 Ð5; Ð2 Ð6; Ð3 Ð7; Ð4 Ð8

Alternate Interior Angles: Ð3 Ð6; Ð4 Ð5

Alternate Exterior Angles: Ð1 Ð8; Ð2 Ð7

Same-side Interior Angles: Ð3 Ð5; Ð4 Ð6

Corresponding Angles Conjecture

If two parallel lines are cut by a transversal, then the corresponding angles are congruent. Also called

______

Alternate Interior Angles Conjecture

If two parallel lines are cut by a transversal, then the alternate interior angles are congruent. Also

called ______

Alternate Exterior Angles Conjecture

If two parallel lines are cut by a transversal, then the alternate exterior angles are congruent. Also

called ______

Parallel Lines Conjecture

If two parallel lines are cut by a transversal, then corresponding angles are ______, alternate interior angles are ______, and alternate exterior angles are ______.

Converse of the Parallel Lines Conjecture

If two lines are cut by a transversal to form pairs of congruent corresponding angles, congruent alternate interior angles, and congruent alternate exterior angles, then the lines are ______.

Same-Side Interior Angles Conjecture

If two parallel lines are cut by a transversal, then the interior angles on the same side of the

transversal are supplementary. Also called ______

Same-Side Exterior Angles Conjecture

If two parallel lines are cut by a transversal, then the exterior angles on the same side of the

transversal are supplementary. Also called ______

Example 1: Using the parallel line conjectures, find the missing angle measures.

a = ______b = ______

c = ______d = ______

e = ______f = ______

g = ______

h = ______i = ______

j = ______k = ______

l = ______m = _____

n = ______

Example 2: Using the converses of the parallel line conjectures, determine which pairs of lines are parallel.

Example 3: Find the value of x.

Example 4: Find the missing angle measures.

a = ______b = ______c = ______d = ______e = ______

f = ______g = ______h = ______i = ______j = ______

k = ______m = ______n = ______p = ______r = ______

s = ______t = ______v = ______w = ______x = ______

y = ______z = ______

pp. 129 – 131 => 1 – 7; 9 - 10

Geometry Lesson 2.6: Special Angles on Parallel LinesPage 1