Question

The perimeter of a rectangle is 86. The length is 15 more than the width. Find the width and length.

Answer 1

Answer:

As you probably know the perimeter of a rectangle is given by the formula 2l + 2w where the length and width are represented by the letters l and w .

In our case,

l = w + 5 ( since the problem states that the length is 5 more than the width)

70 = 2 (w+5) + 2w

70 = 2w + 10 + 2w

4w = 60

w = 15

l = 20

Our length is going to be 20 ft and our width 15 ft.

Explanation:

The perimeter is the sum of the two lengths and the two widths.

So if we let L = the length and W = the width, 2L + 2W = 70

If the length is 5 feet more than the width, then L = W + 5

Substitute W + 5 for L in the first equation--> 2(W + 5) + 2W = 70

2W + 10 + 2W = 70

4W + 10 = 70

4W = 60

W = 15

So L = 20

Plug these numbers back in to the question to make sure that they work.

Have fun.