Definition: Rectangle
A rectangle is a quadrilateral with four right angles.
Area: Rectangle
L = LengthW = WidthArea = L x W sq units
L
W
Example: Rectangle
Area = 9 ft x 3 ftArea = 27 sq ft
3 ft
9 ft
Definition: Square
A square is a quadrilateral with four congruent sides and four
right angles.
Area: Square
S = Length of each sideArea = S x S sq units
S
Example: Square
Area = 8 cm x 8 cmArea = 64 sq cm
8 cm
Definition: Triangle
A triangle is a polygon with three sides.
Area: Triangle
B = BaseH = HeightArea = ½ B x H sq units
B
H
B
H
Example: Triangle
Area = ½ x 12 ft x 6 ftArea = 36 sq ft
12 ft
6 ft
Definition: Trapezoid
A trapezoid is a quadrilateral with only two sides parallel.
Area: Trapezoid
B1 = Base 1B2 = Base 2H = HeightArea = ½ x (B1 + B2) x H sq units
B2
B1
H
Example: Trapezoid
Area = ½ x (4m + 8m) x 5 mArea = 30 sq m
8 m
5 m
4 m
Definition: Circle
A circle is a set of all points in a plane that are an equal distance from its
center.
Area: Circle
r = radiusArea = r 2 sq units
r
Example: Circle
Area = r 2 sq units 3.14Area = 3.14 x (6 in.)2
Area = 3.14 x 36 sq in.Area = 113.04 sq in.
6 in.
Try these problems on
your own.
Find the area of the rectangle below.
Area = 7 ft x 5 ftArea = 35 sq ft
5 ft
7 ft
Find the area of the square below.
Area = 11 cm x 11 cmArea = 121 sq cm
11 cm
Find the area of the figure below.
Area = ½ x 9 ft x 4 ftArea = 18 sq ft
9 ft
4 ft
Find the area of the figure below.
Area = ½ x (7m + 11m) x 6 mArea = 54 sq m
11 m
6 m
7 m
Find the area of the circle below.
Area = r 2 sq units 3.14Area = 3.14 x (8 in.)2
Area = 3.14 x 64 sq in.Area = 200.96 sq in.
8 in.
Find the area of the rectangle below.
Area = 2.7 ft x 4.5 ftArea = 12.15 sq ft
2.7 ft
4.5 ft
Find the area of the square below.
Area = 6.5 cm x 6.5 cmArea = 42.25 sq cm
6.5 cm
Find the area of the figure below.
Area = ½ x 7.8 ft x 3.1 ftArea = 12.09 sq ft
7.8 ft
3.1 ft
Find the area of the figure below.
Area = ½ x (3.6m + 8.4m) x 6.2 mArea = 37.2 sq m
8.4 m
6.2 m
3.6 m
Find the area of the circle below.
Area = r 2 sq units 3.14Area = 3.14 x (17 in.)2
Area = 3.14 x 289 sq in.Area = 907.46 sq in.
17 in.