DefinitionDefinitionAA transversal transversal is a line that intersects 2 is a line that intersects 2 or more coplanar lines at different points.or more coplanar lines at different points.t

m

n

Line t intersects coplanar lines m and n, so t is a transversal.

Draw a picture of 2 coplanar lines m and n (not parallel) with transversal t intersecting them.

1 234

5 678

Which of the numbered angles are interior angles and which ones are exterior angles?

Discuss with your partner.

Mr. Bystrzyckihttp://www.mrandmmeb.com/unit-2-parallel-lines.html

Types of Angles Made by two Types of Angles Made by two lines and a Transversallines and a Transversal

Corresponding anglesCorresponding angles are two are two angles that are on the same side of angles that are on the same side of the transversal, same side of the two the transversal, same side of the two lines.lines.

same sidesame side

t

m

n

1 234

5 678

Name another pair of corresponding angles to your partner.____ and ____ are corresponding angles.

5 14 83 7

Same side interior anglesSame side

interiort

m

n

1 234

5 678

are two angles that are on the same side of the transversal, and inside the two lines.

same side inside

Which other pair of angles do you think are same side interior angles? Why? Discuss with your partner

____ and ____ are same side interior angles because ______________.

Describe this pair of angles.

4 5

Alternate interior anglesAlternateinteriort

m

n

1 234

5 678

are on different sides of the transversal, and inside the two lines.

insidedifferent

Which other pair of angles do you think are alternate interior angles? Why? Discuss with your partner

____ and ____ are alternate interior angles because ______________.

Describe this pair of angles.

3 5

Alternate exterior anglesAlternateexteriort

m

n

1 234

5 678

are on different sides of the transversal, and outside the two lines.

outside

different

Which other pair of angles do you think are alternate exterior angles? Why? Discuss with your partner

____ and ____ are alternate exterior angles because ______________.

What do you think this pair of angles is called?

2 8

Same side exterior anglesSame sideexteriort

m

n

1 234

5 678

are on same sides of the transversal, and outside the two lines.

outside

same

Which other pair of angles do you think are same side exterior angles? Why? Discuss with your partner

____ and ____ are same side exterior angles because ______________.

What do you think this pair of angles is called?

2 7

t

m

n

1 234

5 678

r9 10

121113 14

1615

Jack says that 9 and 15 are same side interior angles? Is he correct? Why or why not?Lori says that9 and 2 are same side

exterior angles? Is she correct? Why or why not?

Parallel LinesParallel Lines

C

YN

I

A

T H

G

YH is parallel to CAYH is also parallel to NGYH is not parallel to AI. These are called skew linesWhat is the difference between parallel lines and skew lines? TPS.

Parallel lines are lines that never intersect that are in the same plane.Skew lines are lines that never intersect that are NOT in the same plane.

Skew lines are 3-d