Question

the perimeter of a rectangle is 140 cm.If the breadth of the rectangle is 40 cm ,find it's length is.Also find the area of the rectangle​

Answer 1

Answer :

• Length of Rectangle = 30 cm.
• Area of Rectangle = 1200 sq.cm.

Explanation :

Given :

• Perimeter of Rectangle = 140 cm.
• Breadth of Rectangle = 40 cm.

To Find :

• Length and Area of Rectangle.

Solution :

First, Let's Calculate Length.

We know that,

❖ Perimeter of Rectangle = 2(l + b).

⇒ 2(L + 40) = 140 cm.

⇒ 2L + 80 = 140 cm.

⇒ 2L = 140 - 80.

⇒ 2L = 60.

⇒ L = 60 ÷ 2.

⇒ L = 30 cm.

Therefore, Length of Rectangle = 30 cm.

Now, Let's Calculate Area.

❖ Area of Rectangle = l × b.

⇒ Area = 30 × 40.

⇒ Area = 1200 sq.cm.

Therefore, Area of Rectangle = 1200 sq.cm.

Answer 2

Step-by-step explanation:

$\frak Given = \begin{cases} &\sf{Perimeter\ of\ the\ rectangle\ =\ 140cm.} \\ &\sf{Breadth\ of\ the\ rectangle\ =\ 40cm.} \end{cases}$

To find:- We have to find the length and the area of the rectangle ?

☯️ First let's we find the length of the rectangle. And after finding the length then we easily find the area of the rectangle.

So let's do !!

__________________

$\frak{\underline{\underline{\dag As\ we\ know\ that:-}}}$

$\sf\pink{\underline{\boxed{\sf Perimeter_{(rectangle)}\ =\ 2(l\ +\ b).}}}$

__________________

$\frak{\underline{\underline{\dag By\ substituting\ the\ values,\ we\ get:-}}}$

$\sf : \implies {140\ =\ 2(l\ +\ 40)} \\ \\ \sf : \implies {140\ =\ 2l\ +\ 80} \\ \\ \sf : \implies {140\ -\ 80\ =\ 2l} \\ \\ \sf : \implies {60\ =\ 2l} \\ \\ \sf : \implies {\cancel \dfrac{60}{2}\ =\ l} \\ \\ \sf : \implies {30\ =\ l} \\ \\ \sf : \implies {\purple{\underline{\boxed{\bf Length\ =\ 30cm.}}}}\bigstar$

Hence:-

$\sf \therefore {\underline{The\ required\ length\ of\ the\ rectangle\ is\ 30cm.}}$

☯️ Now, we get the length of the rectangle that is 30cm. So now we will find the area of the rectangle.

__________________

$\frak{\underline{\underline{\dag As\ we\ know\ that:-}}}$

$\sf\pink{\underline{\boxed{\sf Area_{(rectangle)}\ =\ l\ ×\ b.}}}$

__________________

$\frak{\underline{\underline{\dag By\ substituting\ the\ values,\ we\ get:-}}}$

$\sf : \implies {Area_{(rectangle)}\ =\ 30\ ×\ 40} \\ \\ \sf : \implies {\purple{\underline{\boxed{\bf Area\ =\ 1200sq.cm.}}}}\bigstar$

Hence:-

$\sf \therefore {\underline{The\ required\ area\ of\ the\ rectangle\ is\ 1200sq.cm.}}$