Question

The length of a rectangle is 10 inches more than its width. The perimeter is 60 inches. What is the length of the rectangle?

Answer 1

The length must be 20 inches.

Explanation:

Start with L = W + 10 for an algebraic expression for Length.
Perimeter is 2L + 2W in a rectangle, so write 2(W+10) + 2W = 60.
Now, solve:
`2W+20+2W= 60`

`4W + 20 = 60`

`4W = 40`

`W = 10` inches so L = 10 + 10 or 20 inches.