Download Parallel lines

I heard we have to make a
bunch of note cards again.
Yeah, probably one for every
type of angle formed by parallel
lines cut by a transversal.
I love math!
At least we don’t have to memorize
everything. The note cards are great
on tests!
Parallel lines are lines in the same plane that never intersect.
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A transversal is a line that intersects two or more
lines in a plane at different points.
There are eight angles formed by the transversal
intersecting the lines.
Intersecting lines are lines that cross each other. They have
a point in common.
A transversal can also intersect intersecting lines.
Eight angles are still formed.
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Alternate Interior Angles
• opposite sides of the transversal
• both angles are interior angles
• do NOT share a vertex
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Identify a pair of alternate interior
angles.
WHITE NOTE CARD:
Alternate Interior Angles
• opposite sides of the transversal
• both angles are interior angles
• do NOT share a vertex
X
0
X
0
Consecutive Interior Angles
• same side of the transversal
• both angles are interior angles
• do NOT share a vertex
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Identify a pair of consecutive interior
angles.
WHITE NOTE CARD:
Consecutive Interior Angles
• same side of the transversal
• both angles are interior angles
• do NOT share a vertex
0
0
X
X
Corresponding Angles
• same side of the transversal
• one interior and one exterior angle
• do NOT share a vertex
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Identify a pair of corresponding
angles.
WHITE NOTE CARD:
Corresponding Angles
• same side of the transversal
• one interior angle, one exterior angle
• do NOT share a vertex
☺
X
0
☺
X
0
Alternate Exterior Angles
• opposite sides of the transversal
• both exterior angles
• do NOT share a vertex
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8
7
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4
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Identify a pair of alternate exterior
angles.
WHITE NOTE CARD:
Alternate Exterior Angles
• opposite sides of the transversal
• both angles are exterior angles
• do NOT share a vertex
0
X
0
X
Consecutive Exterior Angles
• same side of the transversal
• both exterior angles
• do NOT share a vertex
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3
8
7
2
4
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6
Identify a pair of consecutive exterior
angles.
WHITE NOTE CARD:
Consecutive Exterior Angles
• same side of the transversal
• both angles are exterior angles
• do NOT share a vertex
0
0
X
X
If two parallel lines are cut by a transversal, then . . .
• alternate interior angles are congruent.
• consecutive interior angles are supplementary.
• corresponding angles are congruent.
• alternate exterior angles are congruent.
• consecutive exterior angles are supplementary.
COLORED NOTE CARD:
If two parallel lines are cut by a transversal, then . . .
• alternate interior angles are congruent.
• consecutive interior angles are supplementary.
• corresponding angles are congruent.
• alternate exterior angles are congruent.
• consecutive exterior angles are supplementary.
If the lines cut by a transversal are NOT parallel,
then no relationship exists between the pairs
of angles EXCEPT vertical angles. Vertical angles
are always congruent.
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a // b and c is the transversal.
Find the measure of each angle. Explain how you
determined the measure.
c
100°
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a
4
b
x // y and z is the transversal. What other angle
measures can you find?
z
1
95°
x
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7
y
5
6
Are we done
with the note
cards yet?
Yes, now it’s time
to solve some
equations!!!