1. Area & Perimeter

2. Page ________ of Notebook Title: Area and Perimeter Title: Area and Perimeter Objective: Find Area and Perimeter Objective: Find Area and Perimeter Essestial Question: How do I find area and perimeter of common polygons and circles? Essestial Question: How do I find area and perimeter of common polygons and circles?

3. Perimeter of a Polygon The perimeter of any polygon is the sum of the measures of the line segments that form its sides. Perimeter is measured in linear units. Perimeter of a Triangle a b c The perimeter P of a triangle with sides of lengths a, b, and c is given by the formula: P = a + b + c.

4. 9.4 – Perimeter, Area, and Circumference Perimeter of a Rectangle w l The perimeter P of a rectangle with length l and width w is given by the formula: P = 2l + 2worP = 2(l + w). Perimeter of a Square The perimeter P of a square with all sides of length s is given by the formula: s s P = 4s.

5. 9.4 – Perimeter, Area, and Circumference Area of a Polygon The amount of plane surface covered by a polygon is called its area. Area is measured in square units. Area of a Rectangle The area A of a rectangle with length l and width w is given by the formula: w l A = l w. Area of a Square s s The area A of a square with all sides of length s is given by the formula: P = s 2.

6. 9.4 – Perimeter, Area, and Circumference Area of a Parallelogram The area A of a parallelogram with height h and base b is given by the formula: b h A = bh. Area of a Trapezoid The area A of a trapezoid with parallel bases b 1 and b 2 and height h is given by the formula: b2b2 h b1b1 A = (1/2) h (b 1 + b 2 )

7. 9.4 – Perimeter, Area, and Circumference Area of a Triangle The area A of a triangle with base b and height h is given by the formula: h b A = (1/2) b h

8. 9.4 – Perimeter, Area, and Circumference Circumference and Area of a Circle The circumference C of a circle of diameter d is given by the formula: or where r is a radius. d r The area A of a circle with radius r is given by the formula:

9. Perimeter of a Rectangle To calculate the perimeter of an object or space, you will need to add the length and width, then multiply by 2. ( 2 + 4 ) x 2 = ______ It means the same as: (2 + 4) + (2 + 4) = ________ 2 4

10. Try to find the perimeter of these rectangles. 1 2 2 3 3 45 6

11. Perimeter of a Square To find the perimeter of a square, multiply the side by 4. 3 x 4 = ___ 3

12. Find the perimeter of these squares. 5 12 25 8 16

13. Perimeter of a Triangle To calculate the perimeter of a triangle you will need to add the sides. 3 + 4 + 5 = ______ 3 4 5

14. Find the perimeter of these triangles. 5 5 5 3 4 5 3 3 3 6 8 10

15. Area of a Rectangle The area of a rectangle is determined by multiplying length x width. 2 x 4 = ______ 2 4

16. Area of a Square or Rectangle 2 x 4 = 8 2 4

17. Find the area of these rectangles. 1 2 2 3 3 45 6

18. Area of a Square You find the area of a square by multiplying the side by itself. 3

19. Find the area of these squares. 5 12 25 8 16

20. Area of a Triangle Finding the area of a triangle is different. Area of a triangle = ½ (base x height) ***(Base x height) is the same as (length x width).*** 3 4

21. Area of a Triangle Sometimes it makes it easier to remember if you can imagine it like this: 3 4 A triangle is half of a rectangle or square. This is because the base (4) x the height (3) would be the same as the length x the width of a rectangle.

22. Find the area of these triangles. 5 7 3 4 2 3 6 8