Find the Area of a rectangle if *
length= a+2
breadth=a+14
Answers
Step-by-step explanation:
The rectangle ABCD has 8 such squares. Therefore, its area is 8 sq cm. Similarly we can find the areas of the other rectangles by counting the number of squares. We also note the length and breadth of each rectangle and write in the table below:
Rectangle
ABCD
LMNO
PQRS
Area
8 sq. cm
12 sq. cm
6 sq. cm
Length
4 cm
4 cm
2 cm
Breadth
2 cm
3 cm
3 cm
Length × Breadth
4 cm × 2 cm = 8 cm2
4 cm × 3 cm = 12 cm2
2 cm × 3 cm = 6 cm2
In each case we observe the length × breadth = Area of the rectangle.
Therefore, area of rectangle = length × breadth = l × b sq. units
From the above multiplication, we get the following facts:
Length of the rectangle = Area of the RectangleBreadth of the Rectangle
Breadth of the rectangle = Area of the RectangleLength of the Rectangle
Consider the following figures:
(i)
Area of a Rectangle
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Area of each small square = 1 sq cm
Area of rectangle in figure 1 by counting the squares = 6 sq. cm
Area = 6 square cm
Length of rectangle = 3 cm
Breadth of rectangle = 2 cm
Area = 3 × 2 = 6 sq. cm
(ii)
Area of a Rectangle
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Area of each small square = 1 sq cm
Area of rectangle in figure 2 by counting the squares = 10 sq. cm
Area = 10 square cm
Length of rectangle = 5 cm
Breadth of rectangle = 2 cm
Area = 5 × 2 = 10 sq. cm
Hence, area of rectangle = length × breadth
A = l × b where, A is the area, l and b are length and breadth of a rectangle.
Let us find the area of a rectangle having length 5 cm and breadth 4 cm.
Area of Rectangle
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From the above figure, it is clear that we can divide this rectangle into 20 squares of sides 1 cm each. So, the area = 20 cm2
Thus the area of the rectangle = 5 cm × 4 cm
= 20 cm2
So when we multiply its length and breadth we get the area of the rectangular