1. 6.1 POLYGONS

2. VOCABULARY Polygon: plane figure formed by three or more segments (called sides). Diagonal: segment that joins 2 non- consecutive vertices

3. CLASSIFYING POLYNOMIALS Name# of SidesSketch Triangle Quadrilateral Pentagon Hexagon Heptagon Octagon Nonagon Decagon

4. EXAMPLE 1 Is the figure a polygon? Explain your reasoning.

5. QUADRILATERALS Quadrilateral Interior Angles Theorem The sum of the measures of the interior angles of a quadrilateral is 360°

6. EXAMPLE 2 Find the measure of the missing angle within each quadrilateral.

7. 6.2 PROPERTIES OF PARALLELOGRAMS Parallelogram: quadrilateral with BOTH pairs of opposite sides parallel

8. THEOREMS ABOUT PARALLELOGRAMS 1)If a quadrilateral is a parallelogram, then its opposite sides are congruent. 2)If a quadrilateral is a parallelogram, then its opposite angles are congruent. 3)If a quadrilateral is a parallelogram, then its consecutive angles are supplementary.

9. EXAMPLE 1 FGHJ is a parallelogram. Find JH and FJ.

10. EXAMPLE 2 PQRS is a parallelogram. Find the missing angle measures.

11. YOU TRY IT… Find the missing side lengths or angle measures as indicated.

12. ONE MORE THEOREM… If a quadrilateral is a parallelogram, then its diagonals bisect each other. REMEMBER: to BISECT a segment means to divide the segment into two congruent segments.

13. EXAMPLE 3 TUVW is a parallelogram. Find TX.