Grade Six Mathematics
Hello Boys and Girls,
I trust your week at school went well. In our previous session, we delved into the notion of perimeter and triangles, engaging in exercises involving perimeter calculations. This week, we'll shift our focus to exploring the concept of area in squares and rectangles. Let's get started.
Area
The area of a shape is the space enclosed within the perimeter or the boundary of a given shape. It is measured in square units such as square centimeters (cm²) or square meters (m²).
Let's explore the steps by which we determine the area of a square.
Area of Square
As previously mentioned in our lesson, in the case of a square, both the length and breadth are equal and often referred to as sides of equal measure. As such, the formula for calculating the area of a square is:
Formula: Area of square = L x L
Or
Side x Side Let’s apply this formula to an example:
Example 1:
Calculate the area of a square of side 7cm. Area of square = Length x Length
= 7cm x 7cm
= 49cm2
Ok boys and girls, let’s now apply what we have learned by completing the exercise below:
Exercise 1
1. Calculate the area of a square of side 11cm.
2. Calculate the area of a square ply of side 14m.
3. Calculate the area of a square table of side 9cm.
4. Calculate the area of a square field of side 25cm.
5. If one side of a square rug is 50m, calculate the area of the rug.
Excellent work, pupils! Let’s move on.
Consider this scenario: when provided with the area of a square and tasked with determining the length of one of its sides, what steps should we take? Reflect on this for a while.
Now, let’s examine the steps in calculating such:
Given the area of a square to find the length of one side
To find for one side of a square given the area, find the square root of the area.
Example 1:
If the area of a square is 16cm2, calculate the length of one side of the square.
Length of one side= √16 = 4cm
It’s that simple!
Let’s work on a few:
Good job, boys and girls!
We’ll now examine the concept of finding the area of another plane shape. Can you guess what shape it is?
Yes! It’s the rectangle!
Area of a rectangle
In a previous lesson, we learned that a rectangle is a two-dimensional shape in which the opposite sides are parallel and equal to each other and all four angles are right angles.
So, how do we calculate the area of a rectangle? Let’s examine the formula below:
Formula:
Area of rectangle= Length x Breadth
Let’s now apply this formula to an example.
Example 1:
Calculate the area of a rectangle with a length of 6cm and a breadth of 4cm. Length= 6cm
Breadth= 4cm
Area of rectangle = Length x Breadth
= 6cm x 4cm Area = 24cm2
Now, boys and girls, it’s your time to work! Complete the table below:
Exercise 3
Great job, boys and girls!
If you're provided with the area and width of a rectangle and tasked with determining the length, what would you do?
Let’s find out:
Exercise 2
Find one side of the following squares given the area:
Given the area and breadth of a rectangle to calculate the length
To calculate the length when given the area and breadth of a rectangle, we apply the following formula:
Length = Area ÷ Breadth