Question

find the area of a rectangle whose perimeter is 360 cm and length is twice of its breadth ​

Answer 1

Let the breadth be B.

Perimeter of rectangle = 2(l+b)

360 = 2(100+B)

360 = 200 + 2B

360 - 200 = 2B

160 = 2B

80 = B

or B = 80 cm

Check:

Perimeter of rect. = 2(l+b)

360 = 2(100+80)

360 = 2 x 180

360 = 360

LHS = RHS

Hence, the breadth of rectangle = 80 cm

Answer 2

$\rule{300}{2}$

$\huge\mathbb{ANSWER}$

$\bold{PERIMETER \: = \: 360 \: cm}$

$\bold{LET \: BREADTH \: BE \: x}$

$\bold{THEN, \: LENGTH \: = \ 2x}$

PERIMETER = 2(L+B)

360=2(x+2x)

360=2(3x)

360=6x

$x = \frac{360}{6} \\ = 60 \: cm$

Breadth=x=60 cm

Length=2x=2×60=120cm

$\huge\bold\red{THANK YOU }$