The perimeter of the rectangle is the sum of the length of all its sides.
For example, if the sides of the rectangle are A,B,CandD, its perimeter will be AB+BC+CD+DA. It is customary to indicate the perimeter by the letter P.
Important to remember!
Rectangles have two pairs of opposite, parallel and equal sides. Therefore, it is enough to know the length of two coincident sides to calculate their perimeter.
Examples with solutions for Perimeter of a Rectangle
Exercise #1
Look at the following rectangle:
Find its perimeter.
Video Solution
Step-by-Step Solution
Since in a rectangle all pairs of opposite sides are equal:
AD=BC=5
AB=CD=9
Now we calculate the perimeter of the rectangle by adding the sides:
5+5+9+9=10+18=28
Answer
28
Exercise #2
Look at the rectangle below.
Side AB is 2 cm long and side BC has a length of 7 cm.
What is the perimeter of the rectangle?
Video Solution
Step-by-Step Solution
Since in a rectangle every pair of opposite sides are equal to each other, we can claim that:
AB=CD=2
AD=BC=7
Now we can add all the sides together and find the perimeter:
2+7+2+7=4+14=18
Answer
18 cm
Exercise #3
Look at the rectangle below.
Side AB is 4.8 cm long and side AD has a length of 12 cm.
What is the perimeter of the rectangle?
Video Solution
Step-by-Step Solution
In the drawing, we have a rectangle, although it is not placed in its standard form and is slightly rotated, but this does not affect that it is a rectangle, and it still has all the properties of a rectangle.
The perimeter of a rectangle is the sum of all its sides, that is, to find the perimeter of the rectangle we will have to add the lengths of all the sides. We also know that in a rectangle the opposite sides are equal. Therefore, we can use the existing sides to complete the missing lengths.
4.8+4.8+12+12 = 33.6 cm
Answer
33.6 cm
Exercise #4
Look at the rectangle below.
Side DC has a length of 1.5 cm and side AD has a length of 9.5 cm.
What is the perimeter of the rectangle?
Video Solution
Step-by-Step Solution
Since in a rectangle every pair of opposite sides are equal to each other, we can claim that:
AD=BC=9.5
AB=CD=1.5
Now we can add all the sides together and find the perimeter:
1.5+9.5+1.5+9.5=19+3=22
Answer
22 cm
Exercise #5
Look at the rectangle below:
Calculate its perimeter.
Video Solution
Step-by-Step Solution
Since in a rectangle every pair of opposite sides are equal to each other, we can claim that:
AB=CD=10
BC=AD=7
Now let's add all the sides together to find the perimeter of the rectangle: