Question

The breadth of a
of a triangle is 4/5 of its
length. If the perimeter of the rectangle is180cm, then find
its length and breadth.pls answer.​

Answer 1

Correct Question :-

The breadth of a rectangle is 4/5 of its length. If the perimeter of the rectangle is 180 cm . Then find its length and breadth.

Given :

• The breadth of a rectangle is 4/5 of its length.
• Perimeter of the rectangle is 180 cm.

To find :

• Length and breadth of the rectangle.

Solution :

Consider,

• Length of the rectangle = x cm
• Breadth of the rectangle = y cm

According to the 1st condition :-

• The breadth of a rectangle is 4/5 of its length.

$\to\sf{y=\dfrac{4}{5}\times\:x}$

$\to\sf{y=\dfrac{4x}{5}...........(1)}$

According to the 2nd condition :-

• Perimeter of the rectangle is 180 cm.

$\to\sf{2(x+y)=180}$

$\to\sf{x+y=90}$

$\to\sf{x+\dfrac{4x}{5}=90\:[put\:y=\dfrac{4x}{5}\: from\:eq(1)]}$

$\to\sf{\dfrac{9x}{5}=90}$

$\to\sf{9x=90\times\:5}$

$\to\sf{x=\dfrac{90\times\:5}{9}}$

$\to\sf{x=50}$

• Length = 50 cm

Now put x = 50 in eq (1) for getting the value of y.

$\to\sf{y=\dfrac{4x}{5}}$

$\to\sf{y=\dfrac{4\times\:50}{5}}$

$\to\sf{y=40}$

• Breadth = 40 cm

Therefore , the length of the rectangle is 50 cm & the breadth of the rectangle is 40 cm.

Answer 2

ANSWER :–

▪︎Length of rectangle is 50 cm and breadth of rectangle is 40 cm.

GIVEN :–

• The breadth of a rectangle is 4/5 of its length.

• Perimeter of the rectangle is 180cm.

TO FIND :–

• Length and breadth of rectangle = ?

SOLUTION :–

• Let the Length of rectangle is 'x' .

• So that , Breadth = (⅘)x

• We know that –

$\\ \longrightarrow { \bold{perimeter \: \: of \: \: rectangle = 2(length \: + \: breadth)}}$

• According to the question –

$\\ \implies { \bold{180 = 2 \left(x \: + \: \dfrac{4}{5} x \right)}}$

$\\ \implies { \bold{180 = 2 \left( \: \dfrac{5 + 4}{5} \right)x}}$

$\\ \implies { \bold{180 = 2 \left( \: \dfrac{9}{5} \right)x}}$

$\\ \implies { \bold{180 = \left( \: \dfrac{18}{5} \right)x}}$

$\\ \implies { \bold{ \dfrac{180 \times 5}{18}= x}}$

$\\ \implies { \bold{ 10 \times 5 = x}}$

$\\ \implies { \bold{ x = 50 \: cm}}$

• Hence , Length of rectangle is 50 cm.

$\\ \implies { \bold{ Now \: \: breadth = \left( \dfrac{4}{5} \right) \times 50}}$

$\\ \implies { \bold{ Breadth = 4 \times 10}}$

$\\ \implies { \bold{ Breadth = 40 \: cm}}$

• Hence , Breadth of rectangle is 40 cm.