Suppose Xinwei want to put a fence around a rectangular field, where the width (w) is three times the length (l). Give an expression for the perimeter of the field in terms of its length (l).

P = 8 l

Step-by-step explanation:

Let's consider a rectangular field with dimensions:

We know that the width (w) is three times the length (l), that is,

w = 3 l   [1]

We can calculate the perimeter (P) of a rectangle using the following expression.

P = 2 l + 2 w   [2]

If we replace [1] in [2], we get,

P = 2 l + 2 (3 l)

P = 2 l + 6 l

P = 8 l

answ9x x 3=

step-by-step explanation: