8-3 Notes by samuelcwallace

VIEWS: 304 PAGES: 2

									                   8-3 Areas of Other Figures


Obj: To find the area of trapezoids and other figures.



KEY TERMS:
Bases of a Trapezoid - the sides that are parallel in a trapezoid.

Height of a Trapezoid – the length of the perpendicular segment that connects
the bases.



FORMULA FOR AREA OF A TRAPEZOID:
                                    1
                              A=      h(b1 + b2 )
                                    2
EXAMPLE PROBLEMS:
                 9.5 m
1.
                                                         1
                                                  A=         h(b1 + b2 )
                 4.4 m                                   2
                                   4.5 m
     5m                                                  1
                                                  A=         4.4 9.5 + 6
                                                         2

                                                  A = 2.2 15.5
                  6m
                                                         A = 34.1 ����2
Base 1 = 9.5 m

Base 2 = 6 m

Height = 4.4 m
             6 cm
  2.
                                                         1
                                 7.2 cm             A = ℎ ����1 + ����2
                                                         2
6 cm
                                                         1
                                                    A = (6) (10+6)
                                                         2

                                                    A = (3) (16)
                    10 cm
                                                    A = 48 ��������2

  Height = 6 cm

  Base 1 = 10 cm

  Base 2 = 6 cm

               15 ft
  3.

                    9 ft.
  12 ft.                                    12 ft



                       27 ft.


  Here we have an irregular hexagon formed by a rectangle and a trapezoid. If
  we find the area of each of the figures separately and then add them together,
  we can find the area of the entire figure.

  Area of Rectangle                                 Area of Trapezoid
                                                         1
  A = (base)(height)                                A = ℎ(����1 + ����2 )
                                                         2

                                                         1
  A = (12)(15)                                      A = (12)(12+3)
                                                         2

  A = 180 �������� 2                                             A = (6)(15)

                                                    A = 90 �������� 2
  Area of Entire Figure

  A = Rectangle + Trapezoid

  A = 180 + 90 = 270 ��������.2

								
To top