6th Grade Math Textbook, Progress

Update your skills. See page 25.

Area of Rectangles and Squares

13-9

What is the area of a square mirror What is the area of a wall

that measures 9.5 cm on each side? that measures 16


2

3 
ft by 10

1

2 
ft?

First estimate: 10 cm10 cm100 cm^2 First estimate: 17 ft11 ft187 ft^2

Then find the area. Then find the area.

Ass A
w

A9.5 cm9.5 cm A 16 
^23 
ft 10 
^12 
ft

25 7

A90.25 cm^2 A

5

3

(^0)
ft
2
2
(^1)
ft175 ft 2
1 1
The area of the
mirror is 90.25 cm^2.
The area of the wall
is 175 ft^2.
Think
90.25 cm^2 is
close to 100 cm^2.
Think
175 ft^2 is close
to 187 ft^2.
To find the area of more complex figures
divide the figure into squares and rectangles.

Find the area of each rectangle
and square.
Rectangle ABCI:A4 m8 m 32 m^2
Square DEJI: A(3 m)^2  9 m^2
Rectangle IFGH:A8 m 2 m 16 m^2

Add to find the area of the entire figure.
A 32 m^2  9 m^2  16 m^2  57 m^2
Study this example.
Find the area of a rectangle that is 3

1
4
feetby 24 inches.
Aw
A 3

1
4
^2 A ^2 A^6

1
2
ft
(^132)
4
The area of a polygon is the number of square units
that cover its surface. The square units may be square
centimeters, square meters, square inches, and so on.
The dashed red linesshow
how the figure can be
divided into rectangles.
Rename units as feet.
24 inches  2 feet
1 square unit
2 m
8 m
3 m
5 m
4 m
B
A F
J
G
I
H
C
D E
Area of a Square
Area side side
Asss^2
Area of a Rectangle
Area length width
Aww
9 .5 cm
10 ft^12
16 ft^23
2
1
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