Lesson 3-2 Angles and Parallel Lines. Ohio Content Standards:

Lesson 3-2Lesson 3-2Angles and Parallel LinesAngles and Parallel Lines

Ohio Content Standards:

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

Postulate 3.1

Corresponding Angles PostulateIf two parallel lines are cut by

a transversal, then each pair of corresponding angles are

congruent.

Postulate 3.1

Corresponding Angles PostulateIf two parallel lines are cut by

a transversal, then each pair of corresponding angles are

congruent.1

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Theorem 3.1

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.3 4

5 6

Theorem 3.2

Theorem 3.2

Consecutive Interior Angles TheoremIf two parallel lines are cut by a

transversal, then each pair of consecutive interior angles is

supplementary.

Theorem 3.2

Consecutive Interior Angles TheoremIf two parallel lines are cut by a

transversal, then each pair of consecutive interior angles is

supplementary.

3 4

5 6

Theorem 3.3

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.1 2

7 8

Theorem 3.4

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

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Assignment:

Pgs. 136-138 14-34 evens, 48-58 evens