1. Area of Regular and irregular polygons Mrs. Korchmaros

2. Objective I can calculate the area of regular and irregular polygons.

3. What is Area??? Area is the amount of space INSIDE of a shape. The blue space below would be the area of that rectangle~

4. How do we calculate area? We calculate the area by multiplying the shape’s length by the shape’s width. 5 feet (Width) 3 feet (Length) To calculate the area of this shape, we would multiply 3 by 5. The area would be 15 feet squared.

5. Why do we put “squared” after the our answer? When we multiplied 3 by 5, we got an answer of 15. That means we could fit 15 1ft by 1ft “squares” inside this shape. 3 feet (Length) 5 feet (Width) 3 feet (Length) 5 feet (Width)

6. Calculate the Area... 7 inches 3 inches

7. Calculate the Area... Did you multiply 7 by 3? You should have gotten an area of 21 inches squared. There are 21 1” x 1” SQUARES that fit inside this shape. 7 inches 3 inches

8. Calculate the Area 6 feet

9. Calculate the Area If you multiply 6ft x 6ft, you get 36 squared feet. This shape fits 36 1‘by1’ squares. 6 feet

10. Area with Decimals Multiply them like you would the whole numbers. 8.3 x 5.7 = 5.7 feet 8.3 feet

11. Area with Decimals Multiply them like you would the whole numbers. 8.3 x 5.7 = 47.31 feet squared 8.3 feet 5.7 feet

12. Area with Fractions Multiply the length and the width. 7 2/3 x 4 1/6= 1/3 yard 1/2 yard Multiply the length and the width. 1/2 x1/3=

13. Area with Fractions Multiply the length and the width. 1/2 x1/3= 1/6 yds squared 1/2 yard 1/3 yard

14. Area of a Triangle Formula: 1/2b x h To find the size of the space within a triangle (its area), you have to multiply 1/2 the base by the height.

15. Area of a Triangle Since the base is 10, we would take half of that (which is 5) and multiply it by the height which is 12. 5 x 12 = 60 cm squared 12cm (height) 10cm (base)

16. Area of a Triangle Take half the base and multiply it by the height. 16 feet 4 feet

17. Area of a Triangle Did you get 32 feet squared? You are correct!! 4 feet 16feet

18. Area of a Triangle Find the area 15’ 6’

19. Area of a Triangle Find the area 45’ squared 15’ 6’

20. Closure On your white boards, give me two different formulas for area.

21. Closure