Question

the length of a rectangle is two times it's width . the perimeter of the rectangle is 90 cm . the length and breadth are in cm​

Answer 1

Answer:

Let the width(b) of the rectangle be 'x'

Therefore, length(l) of the rectangle = 2x

Perimeter of a rectangle = 90cm

2(l+b) = 90cm

2(2x+x) = 90cm

2×3x = 90cm

6x = 90cm

x = 90/6

x = 15cm (width)

Now, length = 2×x = 2×15 = 30cm

Answer 2

Given :-

Length of the rectangle = Breadth × 2

Perimeter of the rectangle = 90 cm

To Find :-

The length of the rectangle.

The breadth of the rectangle.

Analysis :-

Consider the length and breadth as variables accordingly.

Make an equation and get the value of the breadth.

Multiply the breadth to the length according to the question.

Solution :-

We know that,

• l = Length
• b = Breadth
• p = Perimeter

Let the breadth be 'x', then the length would be '2x'.

By the formula,

$\underline{\boxed{\sf Perimeter \ of \ rectangle=2(Length+Breadth)}}$

Given that,

Length (l) = 2x

Breadth (b) = x

Perimeter (p) = 90 cm

Substituting their values,

$\sf 90=2(2x+x)$

$\sf 90 = 2 (3x)$

$\sf 90=6x$

Finding the value of x,

$\sf x=\dfrac{90}{6}$

$\sf x=15$

Therefore,

Breadth (b) = 15 cm

Length (l) = 2x

= 2 × 15 = 30 cm

Therefore, the length and breadth is 30 cm and 15 cm respectively.