Question

The length of a rectangle is three times its width. If the perimeter of the rectangle is 40 m, find its length and width.

Answer 1

The width would be 5, and the length would be 15.

Explanation:

To solve this problem, first look at the perimeter. If the perimeter of the rectangle is 40m, then we can now solve the problem.

Since we don't know the width or the length, first, say that the width is w.

Width=w

Now, since the length is three times the width, we can write 3w for the length.

Length=3w.

Now, combine like terms.

w+3w+w+3w=40

8w=40

Divide by 8 on both sides.

40/8=5

w=5.

Since now we know that the width is 5, plug in 5 for w.

3(5)=15

w=5

The width would be 5, and the length would be 15.

Hope this helps! Have a great day! :D

Answer 2

• Length = 15 m
• Width = 5 m

Explanation:

Let us assume that,

→ Perimeter = 40 m

→ Width = x

→ Length = 3x

Perimeter of rectangle formula,

→ P = 2(l + w)

Forming the equation,

→ 2(3x + x) = 40

Now the value of x will be,

→ 2(3x + x) = 40

→ 2(4x) = 40

→ 8x = 40

→ x = 40/8

→ [ x = 5 ]

Then the length and width is,

→ Width = x = 5 m

→ Length = 3x = 3(5) = 15 m

Hence, these are the answers.