1. STUDY LINK 3.8 When you are finished checking your study link; start on Math Boxes 3.8

2. I can find the angle measurement sum for any polygon.

3. 1. Draw a large triangle on the blank piece of paper on your desk. 2. Use your protractor to measure each angle; label each angle. 3. Add the measure of the angles and record the sum on our line plot (draw an “X” above the sum for your triangle). MATH MESSAGE

4. Arrange your 3 angles next to each other so they line up. What type of angle have you created? What does this show? TEAR THE THREE ANGLES OFF OF YOUR TRIANGLE

5. DRAW EXAMPLES OF Polygons Not Polygons Convex PolygonsConcave (nonconvex) Polygons

6. Groups of 4 Mrs. H. will assign your group “quadrangle” or “pentagon” JOURNAL PAGES 85-86

7. CLASS DATA (JOURNAL PAGES 87 & 88) GroupGroup MedianGroupGroup Median QuadranglesPentagon

8. Why do you think the measures increase by 180°? How many degrees are in a triangle? Quadrangles divide into _______ triangles. DAY 2 DIVIDING POLYGONS INTO TRIANGLES 2 x 180° = 360° **When drawing lines to divide a polygon into triangles, the lines must go from one vertex to another; they cannot start or end in the middle of the polygon or between the endpoints of the line segments.

9. HOW MANY TRIANGLES CAN BE DRAWN IN A PENTAGON? 3 x 180° = 540°

10. HOW MANY TRIANGLES CAN BE DRAWN IN A HEXAGON? 4 x 180° = 720° Conclusion: When you add another side to the figure, you are able to draw an additional triangle in the figure, which adds 180°. What do you notice about the relationship between the number of sides of the polygon and the number of triangles that can be drawn in it? The number of triangles inside the polygon is 2 less than the number of sides.

11. MATH JOURNAL PAGE 89 (AND MM 94) NameNumber of sides EquationTotal Degrees Triangle Quadrilateral/Quadrangle Pentagon Hexagon Heptagon Octagon Nonagon Decagon Dodecagon

12. 1.Math Journal pages 90-91; tessellations website 2.MM 93 (Left) CENTERS Centers

13. Study Link 3.9 HOMEWORK