Question

In a rectangle length is thrice of breadth and perimeter is 40 cm then what is its area

Answer 1

Step-by-step explanation:

length(l) =3b

breadth(b) =b

perimeter=2(l+b)

40=2(3b+b)

40/2=4b

20=4b

20/4=b

b=5

l=3b

l=15

area=l×b

15×5=75

Answer 2

Answer:

The area of the Rectangle is 75 cm².

Step-by-step explanation:

Given :

Length of the Rectangle = Thrice it's Breadth

Perimeter of Rectangle = 40 cm

To Find :

The Rectangle's area.

Solution :

Consider the -

• Breadth as x
• Length as 3x

Perimeter of Rectangle = 2(Length + Breadth)

$\longrightarrow$ 2(3x + x) = 40

$\longrightarrow$ 6x + 2x = 40

$\longrightarrow$ 8x = 40

$\longrightarrow$ x = 40/8

$\longrightarrow$ x = 5

$\rule{300}{1.5}$

★Value of 3x

$\longrightarrow$ 3 × 5

$\longrightarrow$ 15

Length of the Rectangle is 15 cm and Breadth is 5 cm.

$\rule{300}{1.5}$

Area of the Rectangle = Length × Breadth

$\longrightarrow$ 15 × 5

$\longrightarrow$ 75

$\therefore$ The area of the Rectangle is 75 cm².