Question

The length of a rectangle is three times its width. if the area of the rectangle is 75 in2, find its perimeter.

Answer 1

Answer:

  40 in

Step-by-step explanation:

For a width of w, the length is 3w and the area and perimeter are ...

  A = LW = (3w)(w) = 3w^2

  P = 2(L+W) = 2(3w +w) = 8w

We are given the area, so we can find w to be ...

  75 in^2 = 3w^2

  25 in^2 = w^2 . . . . . divide by 3

  5 in = w . . . . . . . . . square root

Then the perimeter is ...

  P = 8w = 8(5 in) = 40 in