Question

the perimeter of a rectangle is 14 m and its length is 4 m. find its area.​

Answer 1

Answer:

Let, breadth of rectangle is x, then 5x−4 be the length of the rectangle.

Perimeter of rectangle =2(l+b)

⇒40=2(l+b)

⇒40=2(5x−4+x)

⇒40=12x−8

⇒12x=40+8

⇒12x=48

⇒x=

12

48

⇒x=4

Breadth =4 meters

Hence, length =5×4−4=20−4=16m

Therefore, area of rectangle =lb=16×4=64m

2

Answer 2

Answer:

Step-by-step explanation:

Let, breadth of rectangle is x, then 5x−4 be the length of the rectangle.

Perimeter of rectangle =2(l+b)

⇒40=2(l+b)

⇒40=2(5x−4+x)

⇒40=12x−8

⇒12x=40+8

⇒12x=48

⇒x=

12

48