Question

The length of a rectangle is three less than twice the width. The perimeter of the rectangle is 54. What is the length of the rectangle?

Answer 1

17

Explanation:

Use the perimeter formula, P = 2l + 2w, where l is the length and w is width

Since the length of the rectangle is 3 less than twice the width, it can be represented by 2w - 3

Plug in the perimeter, w for the width, and 2w - 3 for the length in the equation:

P = 2l + 2w

54 = 2(2w - 3) + 2w

Distribute the 2 to the parentheses:

54 = 4w - 6 + 2w

Add like terms:

54 = 6w - 6

Solve for w:

60 = 6w

10 = w

So, the width is 10. To find the length, plug in 10 as w into 2w - 3

2w - 3

2(10) - 3

= 17

So, the length is 17.