Question

the length of rectangle is three times its breath.if the perimeter of the rectangle is 40cm,find the length and breadth of the rectangle​

Answer 1

Answer:

$\large{\underline{\boxed{\sf Length = 15 \: cm}}}$

$\large{\underline{\boxed{\sf Breadth = 5 \: cm}}}$

Step-by-step explanation:

Let the breadth of rectangle be x and the length be 3x.

Given that ;

Perimeter of rectangle = 40 cm

⇒ 2(l + b) = 40

⇒ l + b = 40/2

⇒ 3x + x = 20

⇒ 4x = 20

⇒ x = $\sf \dfrac{20}{4}$

⇒ x = 5

Therefore, the dimensions of rectangle are;

• Length = 3x = 3 * 5 = 15 cm
• Breadth = x = 5 cm.

Hence, the length of the rectangle is 15 cm and breadth is 5 cm.

Answer 2

Given:

Perimeter of rectangle = 40

Let the breadth(b) of the rectangle = x

According to question

Length(l) = 3x

We know,

Perimeter of rectangle = 2(l + b)

40 = 2(3x + x)

40 = 2(4x)

40 = 8x

x = $\dfrac{40}{8}$

x = 5

Therefore,

Breadth = x = 5 cm

Length = 3x = 3(5) = 15 cm