Area and Perimeter of Rectangles
Area and Perimeter of Rectangles 3y
30 f 9f
2y
A _____________
A _____________
P _____________
P _____________
18 i
11 f 6 i 1f
3 1/3 y
A _____________
A _____________
P _____________
P _____________
2y 3i
12 f
13.25 f
8f
A _____________
A _____________
P _____________
P _____________
Area and Perimeter of Rectangles
Definition of a rectangle The best definition of a rectangle (for the purposes of this course) is a two-dimensional, foursided figure with opposite sides equal and parallel with all right angles. The two (2) dimensions of a rectangle are referred to as length and width and are abbreviated l, w. It doesn’t matter which is length and which is width as long as each parallel line is labeled the same way. A special kind of rectangle is known as a square which has the added requirement that all four (4) sides are of equal length. (All squares are rectangles but all rectangles are not squares.)
(A)
(B)
Length Width
Width Width
Length
Length
Length Width
Length
The two (2) properties of a rectangle with which this course will be concerned are area and perimeter. The area is the interior portion of either of the above figures and the perimeter is the “border” around the same figures. Prior to calculating either of these properties, all units of measure must be the same. In other words, if the length is measured in feet, the unit of measure for width must also be feet. The formula for finding the perimeter is two (2) times the length plus (2) times the width (2 * Length + 2 * Width (2L + 2W)) and the result is expressed in linear units. The “2” can be factored out of this equation and the formula can be expressed as 2(W + L). The formula for finding the area is Length * Width (LW) and the result is expressed in square units. If the length in Figure A is 12 feet and the width is 2 yards, the first step in calculating the area and perimeter of the rectangle would be to convert 12 feet to yards or 2 yards to feet. 12 feet could be expressed as 4 yards, so the Perimeter would be (2)(4 +2) yards = 12 yards and the area would be (2 yards)(4 yards) = 8 square yards.
30 f 9f
2y
A _____________
A _____________
P _____________
P _____________
18 i
11 f 6 i 1f
3 1/3 y
A _____________
A _____________
P _____________
P _____________
2y 3i
12 f
13.25 f
8f
A _____________
A _____________
P _____________
P _____________
Area and Perimeter of Rectangles
Definition of a rectangle The best definition of a rectangle (for the purposes of this course) is a two-dimensional, foursided figure with opposite sides equal and parallel with all right angles. The two (2) dimensions of a rectangle are referred to as length and width and are abbreviated l, w. It doesn’t matter which is length and which is width as long as each parallel line is labeled the same way. A special kind of rectangle is known as a square which has the added requirement that all four (4) sides are of equal length. (All squares are rectangles but all rectangles are not squares.)
(A)
(B)
Length Width
Width Width
Length
Length
Length Width
Length
The two (2) properties of a rectangle with which this course will be concerned are area and perimeter. The area is the interior portion of either of the above figures and the perimeter is the “border” around the same figures. Prior to calculating either of these properties, all units of measure must be the same. In other words, if the length is measured in feet, the unit of measure for width must also be feet. The formula for finding the perimeter is two (2) times the length plus (2) times the width (2 * Length + 2 * Width (2L + 2W)) and the result is expressed in linear units. The “2” can be factored out of this equation and the formula can be expressed as 2(W + L). The formula for finding the area is Length * Width (LW) and the result is expressed in square units. If the length in Figure A is 12 feet and the width is 2 yards, the first step in calculating the area and perimeter of the rectangle would be to convert 12 feet to yards or 2 yards to feet. 12 feet could be expressed as 4 yards, so the Perimeter would be (2)(4 +2) yards = 12 yards and the area would be (2 yards)(4 yards) = 8 square yards.
