Question

If the area of a rectangle is 84 cm2 and its length is 12cm then find the perimeter of the
rectangle.

Answer 1

Given:

Area of rectangle = 84cm²

Length of rectangle = 12cm

To Find:

Perimeter of rectangle

Solution:

We know that,

Area of rectangle = l × b

84cm² = 12 × b

84/12 = b

7 = b

Now,

We have l = 12 and b = 7

So,

Perimeter of rectangle = 2(l + b)

= 2(12 + 7)

= 2(19)

= 38cm

Hence, the perimeter of rectangle is 38cm.

Answer 2

☆ Solution ☆

Given :-

• The area of a rectangle is 84 cm²

• The length of a rectangle = 12 cm

To Find :-

• The breadth of a rectangle

• The perimeter of rectangle

Step-by-Step-Explaination :-

As we know that :-

Area of the rectangle = l × b

Let,

• The b be 'b'

Where,

• Area of the rectangle = 84 cm²

• l = 12 cm

• b = b

Putting the respective value,

84 = 12 × b

b = 84/12

b = 7

Thus,

The breadth of the rectangle = 7 cm

Now,

As we know that :-

Perimeter of rectangle = 2 ( l + b )

Where,

• l = 12 cm

• b = 7 cm

Putting the respective value,

Perimeter of rectangle = 2 ( 12 + 7 )

Perimeter of rectangle = 2 × 19

Perimeter of rectangle = 38

Thus,

The perimeter of the rectangle = 38 cm