1. Prove Angle Pair Relationships
Section 2.7
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2. In this section… SWBAT: Use the properties of special pairs of angles
Use the facts about angle pairs to find measures of angles
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3. Recall these facts about angles
Right angles have a measure of 90˚
Obtuse angles have angle measures greater than 90˚ and less than 180 ˚
Acute angles have angle measures greater than 0 ˚ and less than 90˚
Straight angles have a measure of 180˚
Complementary angles are 2 angles whose sum equals 90˚
Supplementary angles are 2 angles whose sum equals 180˚
Supplementary angles aren’t necessarily a linear pair
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4. Angles cont. 1 2 Perpendicular lines have an angle measure of 90˚
Linear pairs are two angles that are supplementary and share a common side.
Vertical pairs are angles created by two intersecting lines that are opposite each other. They also have the same angle measure. 1 2
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5. Angles Cont.
Adjacent angles are angles that share a common interior side.
Common side
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6. “New” Theorems
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13. Identify Congruent Pairs of Angles1 3 2
<1 and <2, <1 and <3, and <2 and <3
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14. Identify Congruent Pairs of Angles
<1 & <2, <1 & <3, <1 & <4, <2 & <3, <2 & <4, <3 & <4
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15. Identify Congruent Pairs of Angles
<1 & <3, <4 & <2
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16. Find the measures of the angles and the values of x and y.
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17. Page 127
3-5, 12, 13, 17-21
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