Lesson 3-2 Angles and Parallel Lines

Ohio Content Standards:

Formally define geometric figures.

Ohio Content Standards: Recognize and apply angle relationships in situations involving intersecting lines, perpendicular lines and parallel lines.

Ohio Content Standards: Recognize the angles formed and the relationship between the angles when two lines intersect and when parallel lines are cut by a transversal.

Postulate 3.1

Corresponding Angles Postulate If two parallel lines are cut by a transversal, then each pair of corresponding angles are congruent.

Postulate 3.1 Corresponding Angles Postulate If two parallel lines are cut by a transversal, then each pair of corresponding angles are congruent

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Theorem 3.1

Alternate Interior Angles Theorem If two parallel lines are cut by a transversal, then each pair of alternate interior angles are congruent.

Theorem 3.1 Alternate Interior Angles Theorem If two parallel lines are cut by a transversal, then each pair of alternate interior angles are congruent

Theorem 3.2

Consecutive Interior Angles Theorem If two parallel lines are cut by a transversal, then each pair of consecutive interior angles is supplementary.

Theorem 3.2 Consecutive Interior Angles Theorem If two parallel lines are cut by a transversal, then each pair of consecutive interior angles is supplementary

Theorem 3.3

Alternate Exterior Angles Theorem If two parallel lines are cut by a transversal, then each pair of alternate exterior angles are congruent.

Theorem 3.3 Alternate Exterior Angles Theorem If two parallel lines are cut by a transversal, then each pair of alternate exterior angles are congruent

Theorem 3.4

Perpendicular Transversal Theorem In a plane, if a line is perpendicular to one of two parallel lines, then it is perpendicular to the other.

Theorem 3.4 Perpendicular Transversal Theorem In a plane, if a line is perpendicular to one of two parallel lines, then it is perpendicular to the other. l n m

V 65° R P U S 60° M T N Q

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Assignment: Pgs evens, evens