Question

The perimeter of a rectangle is 30 cm. If its breadth is 3 cm then its length is


please give me the right answer.​

Answer 1

Given :

• The perimeter of the rectangle is 30 cm.
• It's breadth is 3 cm.

To find :

• It's length

We know that,

Perimeter of rectangle = 2 ( length + breadth )

So,

30 = 2 ( length + 3 )

30/2 = length + 3

15 = length + 3

length = 15 - 3

length = 12

Answer 2

Answer :-

The length of rectangle is 12cm.

Step-by-step explanation:

Given that,

• The perimeter of rectangle = 30cm
• The breadth of rectangle = 3cm.

Assumption:

Let us assume the length of rectangle as (x) cm.

We know,

Perimeter of rectangle = 2 ( l + b ),

Where,

• l = length
• b = breadth

A . T . Q,

$\sf{\mapsto \: 2 ( l + b ) = Perimeter}$

$\sf{\mapsto \: 2 ( x+ 3 ) = 30}$

$\sf{\mapsto \: ( x + 3 ) = \dfrac{30}{2}}$

$\sf{\mapsto \: ( x + 3 ) = \cancel{\dfrac{30}{2}}}$

$\sf{\mapsto \: x + 3 = 15}$

$\sf{\mapsto \: x = 15 - 3}$

$\sf{\mapsto \: x = 12}$

We got the value of x as 12.

∴ The length of rectangle is :-

$\sf{\mapsto \: (x) \: cm}$

$\sf{\mapsto \: 12 \: cm}$

Hence, The length of the rectangle is 12cm.