Question

Ms.Cubaj uses a piece of rope that is 40 meters long to make a rectangular garden. The perimeter of the rectangle must be 40. Write a function that represents the area of the rectangle with the length l.

Answer 1

Answer: 20 l - l² .

Explanation:

Answer 2

A function that represent the area of rectangle with length is 20 l - l² .

Explanation:

The total length of rope = L =40 meters

The perimeter of rectangular garden which can be made using rope = p = 40 meters

Let the width of rectangular garden = w meters

And The length of rectangular garden = l meters

Now,

The perimeter of rectangular garden = 2 × Length + 2 × width

I.e p = 2 × l + 2 × w

Or, 40 meters = 2 × l + 2 × w

I.e l + w =
`(40)/(2)`

∴ l + w = 20

Or, w = 20 - l

Now, Again

Let The area of rectangular garden = A = Length × width

Or, A = l × w

Or, A = l × (20 - l)

∴ A = 20 l - l²

So, Area of rectangular garden = A = 20 l - l²

Hence, A function that represent the area of rectangle with length is 20 l - l² . Answer