Title: Warm Up
1Warm Up
Problem of the Day
Lesson Presentation
Lesson Quizzes
2Warm Up Find each area. Round to the nearest
tenth, if necessary. 1. a rectangle with length
10 cm and width 4 cm 2. a parallelogram with
base 18 ft and height 12 ft 3. a triangle with
base 16 cm and height 8 cm 4. a circle with
radius 5 in.
40 cm2
216 ft2
64 cm2
78.5 in2
3Problem of the Day Four squares are placed in a
row, adjacent to one another. The square on the
far left is 12 inches on a side. The perimeter of
each of the other squares is half of the one to
its left. What is the perimeter of the combined
figure?
69 in.
4Additional Example 1A Finding the Area of
Composite Figures by Adding Find the shaded area.
Round to the nearest tenth, if necessary.
5Additional Example 1 Continued Find the shaded
area. Round to the nearest tenth, if necessary.
2 m
8 m
2 m
4 m
6 m
6 m
6Check It Out Example 1 Find the shaded area.
Round to the nearest tenth, if necessary.
7Check It Out Example 1 Continued Find the shaded
area. Round to the nearest tenth, if necessary.
8Additional Example 2 Finding the Area of
Composite Figures by Subtracting
5 ft
Find the shaded area.
6 ft
9 ft
Subtract the area of the triangle
from the area of the rectangle.
12 ft
9Check It Out Example 2
9 in.
Find the shaded area.
5 in.
8 in.
16 in.
area of rectangle A lw 16 8 128 area of
triangle A bh (5 7) (35)
17.5 area of shaded area A 128 - 17.5 110.5
in
1
_
1
1
2
2
2
2
10Additional Example 3 Landscaping Application
6 ft
What is the area of the room floor shown in the
figure? Round to the nearest tenth.
12 ft
12 ft
6 ft
18 ft
To find the area, divide the composite figure
into a square, a rectangle, and a semicircle.
11Additional Example 3 Continued
6 ft
12 ft
12 ft
6 ft
18 ft
12Additional Example 3 Continued
6 ft
What is the area of the room floor shown in the
figure? Round to the nearest tenth.
12 ft
12 ft
6 ft
18 ft
13Check It Out Example 3
What is the area of the stage floor shown in the
figure? Round to the nearest tenth.
14Check It Out Example 3 Continued
area of top rectangle A lw 5 5 25 area
of large rectangle A lw 15 5 75 area of
semicircle A ? r (3.14 7.5 )
(176.6) 88.3 total area A 25 75 88.3
188.3 ft
2
2
2
15Lesson Quizzes
Standard Lesson Quiz
Lesson Quiz for Student Response Systems
16Lesson Quiz Part l
Find the shaded area of each figure. Round to the
nearest tenth, if necessary. 1. 2.
3.
5 ft
17Lesson Quiz Part ll
4. The figure gives the dimensions of a backdrop
for a school play. Find the area of the
backdrop.
18Lesson Quiz for Student Response Systems
1. Find the shaded area of each figure. Round to
the nearest tenth, if necessary. A. 40 ft2
B. 54.1 ft2 C. 14 ft2 D. 68.3 ft2