How to use area and perimeter:
The formula for calculating the perimeter of a rectangle is:
P = (2 x l) + (2 x w) where l stands for length and w stands for width
In a rectangle, opposite sides are congruent, so we can take 2 times the length and 2 times the width because they are the same measure.
The formula for calculating the area of a rectangle is:
A = l x w where l stands for length and w stands for width
Area is how many squares are inside of the rectangle. It is for this reason that the answer to area is in square units.
Sample Math Problems
1. Find the perimeter of the rectangle.
Solution:
P = (2 x l) + (2 x w)
P = (2 x 8) + (2 x 5)
P = 16 + 10
P = 26 cm
P = (2 x l) + (2 x w)
P = (2 x 8) + (2 x 5)
P = 16 + 10
P = 26 cm
2. Find the area of the rectangle
Solution:
A = l x w
A = 8 x 5
A = 40 cm²
3. How much fencing material is required to fence a rectangular playground with sides 5 units and 9 units?
Solution:
Solution:
P = (2 x l) + (2 x w)
P = (2 x 9) + (2 x 5)
P = 18 + 10
P = 28 units
4. A bookmark is 9 cm long and 2 cm wide. What is the area in square centimeters?
A = l x w
A = 9 x 2
A = 18 cm²
