Question

the length of a rectangle is 4 cm more than the breadth . if the perimeter of rectangle is 80cm find the area of the rectangle​

Answer 1

Answer:

The area of the rectangle = 396 cm²

Step-by-step explanation:

Solution :

Let,

The breadth of a rectangle = x

The length of a rectangle = x + 4

The perimeter of rectangle = 80 cm (Given)

The perimeter of rectangle = 2 (length + breadth)

⇒ 2 [(x + 4) + x] = 80

⇒ 2x + 8 + 2x = 80

⇒ 4x + 8 = 80

⇒ 4x = 80 - 8

⇒ 4x = 72

⇒ x = 72/4

⇒ x = 18

The breadth of a rectangle = 18 cm

The length of a rectangle = x + 4

⇒ 18 + 4

⇒ 22

The length of a rectangle = 22 cm

The area of the rectangle = length × breadth

⇒ 22× 18

⇒ 396

The area of the rectangle = 396 cm²

Therefore, The area of the rectangle = 396 cm²

Answer 2

Given :-

The length of a rectangle is 4 cm more than the breadth . if the perimeter of rectangle is 80cm

To Find :-

Area

Solution :-

Let the length be l and breadth be b

Length is 4 cm more than its breadth

l = b + 4 (1)

Now

Perimeter = 2(l + b)

80 = 2(l + b)

• By putting l = b + 4

80/2 = b + 4 + b

40 = 2b + 4

40 - 4 = 2b

36 = 2b

36/2 = b

18 = b

Now, Using 1

l = 18 + 4

l = 22 cm

Area = l × b

Area = 22 × 18

Area = 396 cm²