Angles Formed by Parallel Lines and Transversals

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Angles Formed by Parallel Lines and Transversals
Module 3-1 Notes Angles Formed by Parallel Lines
Transversals Monday August 26th
Holt Geometry
Holt McDougal Geometry
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Warm Up
1) If 2 angles add up to 900, then they are complementary CONVERSE INVERSE CONTRAPOSITIVE 2) What value of y makes the 2 figures similar?
If 2 angles are complementary, then they add up
to 900 If 2 angles dont add up to 900, then
they arent complementary If 2 angles arent
complementary, then they dont add up to 900
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Vocabulary
Transversal A line that intersects 2 coplanar
lines at 2 different points Parallel Lines
lines in the same plane that do NOT intersect
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Example 1 Using the Corresponding Angles
Postulate
Find each angle measure.
A. m?ECF
B. m?DCE
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Try this on your own
Find m?QRS.
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• Alternate Interior Angles
• Alternate Exterior Angles
• Same-Side Interior Angles

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Example 2 Finding Angle Measures
Find each angle measure.
A. m?EDG
B. m?BDG
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Try this on your own
Find m?ABD.
Alt. Interior Angles
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Classwork
m JKL 1270 m BEF
630 m 1 900
m CBY 660