1. Geometry Summary Chapter 1 sections 2-4 8-28-15

2. Midpoint and Congruence Just a reminder, Congruence means identical in size and shape. For two figures to be congruent in geometry, they must both have the exact same angles and dimensions. Midpoint is the middle of a line segment. The two segments created on either side of the midpoint are congruent.

3. Bisector A B C 9 9

4. If AB=7 what is BC? If AC=20, what is BC? If AB=3x+10 and BC=4x+4

5. Bisectors Angles can also be bisected. Angles are bisected by rays or lines or segments. When an angle is bisected, it creates two congruent angles.

6. Adjacent angles Adjacent angles are two angles that share a common ray. Angles ADB and CDB share ray BD The angles must be coplanar The angles may not overlap A B C D

7. Vertical Angles Any two lines that intersect create two pairs of vertical angles. Just remember “Big=Big and Little=Little”  1  3 and  2  4 VERY IMPORTANT 1 3 2 4

8. Complementary and Supplementary Angles Any pair of angles that add up to 90 degrees are complementary. Any pair of angles that add up to 180 degrees are supplementary. Complementary comes first in the alphabet and 90 comes first on the number line. Supplementary comes later in both the alphabet and on the number line.

9. Calculate the missing angles 127⁰ X 90⁰ Y Z

10. Try these…

11. Try these, you may have to draw your own diagram.

12. Try these…

13. Closing… Define: Adjacent angles Vertical angles Complementary angles Supplementary angles Congruent Bisect Midpoint