1. …with a little review C. N. Colon Geometry

2. Proving Triangles Congruent by (AAS, HL)

3. AAS If two angles and a non included side of one triangle are congruent to the corresponding two angles and side of a second triangle, then the two triangles are congruent. HL If the hypotenuse and a leg of one right triangle are congruent to the hypotenuse and corresponding leg of another right triangle, then the triangles are congruent. A BC D E F A BC D E F

4. StatementsReasons Step 1: Mark the Given Step 2: Mark vertical angles Step 3: Choose a Method (SSS /SAS/ASA/AAS/ HL ) Step 4: List the Parts in the order of the method Step 5: Fill in the reasons Step 6: Is there more? AAS Given Vertical Angle Thm AAS Postulate

5. StatementsReasons Step 1: Mark the Given Step 2: Mark reflexive sides Step 3: Choose a Method (SSS /SAS/ASA/AAS/ HL ) Step 4: List the Parts in the order of the method Step 5: Fill in the reasons Step 6: Is there more? HL Given Reflexive Property HL Postulate

6. C. N. Colόn Geometry

7. POLYGONS

8. What does the word “polygon” mean? What is the smallest number of sides a polygon can have? What is the largest number of sides a polygon can have? POLYGONS

9. 10/17/2007 EQ: How do I find the measure of an interior & exterior angle of a polygon? Triangle Quadrilateral Pentagon Hexagon Heptagon Octagon Nonagon Decagon Dodecagon n-gon

10. F AB C DE A VERTEX is the point of intersection of two sides A segment whose endpoints are two nonconsecutive vertices is called a DIAGONAL. CONSECUTIVE VERTICES are two endpoints of any side. Sides that share a vertex are called CONSECUTIVE SIDES. POLYGONS

11. EQUILATERAL - All sides are congruent EQUIANGULAR - All angles are congruent REGULAR - All sides and angles are congruent POLYGONS

13. 10/17/2007 What is the sum of the measures of the interior angles of a triangle? 180° What is the sum of the measures of the interior angles of any quadrilateral?REVIEW: 180° 360°

14. If a convex polygon has n sides, then the sum of the measure of the interior angles is (n-2)(180°) By the way concave is the opposite of convex. A concave polygon has sides that “collapse” inward

15. A)Find the sum of the measures of the interior angles. B)Find the measure of ONE interior angle 540° 108°

16. Exterior Angles Interior Angles

17. In any convex polygon, the sum of the measures of the exterior angles, one at each vertex, is 360°. 1 2 3 4 5

18. 1 3 2

19. 60°

20. 51.4°

21. 185°

22. 30°, 90°, 150°, and 90°

23. n = 6

24. HW: p. 371 #4-20 (mo4) … tomorrow’s HW is the Ch. 9 Review p. 375 # 1-25 (all)