Question

2. The perimeter of a rectangle is 42 cm and its length is double its breadth. Find the length
and breadth of the rectangle.​

Answer 1

Question:-

The perimeter of a rectangle is 42 cm and its length is double its breadth. Find the length and breadth of the rectangle.

Answer:-

• Length = 14 cm
• Breadth = 7 cm

Solution:-

• Perimeter = 42 cm
• Let the length (l) be 2x cm
• Let the breadth (b) be x cm

$\blue{ \boxed{ \red{ \large{perimeter = 2(l + b)}}}}$

$\large{ : \implies \: 2(2x + x) = 42}$

$\large{ : \implies \: 3x = \frac{42}{2} }$

$\large{ : \implies \: 3x = 21}$

$\large{ : \implies \: x = \frac{21}{3} }$

$\large{ : \implies \: x = 7 \: cm}$

• The breadth of rectangle is 7 cm.
• Length = 2x = 2×7 = 14 cm

Answer 2

Let, the breadth be x.

perimeter of rectangle = 2 ( l + b )

⇒ 42 cm = 2 ( 2x + x )

⇒ 42 cm = 2 × 3x

⇒ 42 cm = 6x

⇒ 7 cm = x

length = 2x

= 2 × 7 cm

= 14 cm

breadth = x

= 7 cm