Question

The perimeter of a rectangle is a 128 inches. The width of the rectangle is 4y inches. Find the length of the rectangle in the terms of y?

Answer 1

See a solution process below:

Explanation:

The formula for the perimeter of a rectangle is:

`p = 2(w + l)`

Where:

`p` is the perimeter of the rectangle: 128 inches for this problem.

`w` is the width of the rectangle: `4y` for this problem.

`l` is the length of the rectangle: what we are solving for in this problem.

Substituting and solving for `l` gives:

`128"in" = 2(4y + l)`

`(128"in")/color(red)(2) = (2(4y + l))/color(red)(2)`

`64"in" = (color(red)(cancel(color(black)(2)))(4y + l))/cancel(color(red)(2))`

`64"in" = 4y + l`

`64"in" - color(red)(4y) = 4y - color(red)(4y) + l`

`64"in" - 4y = 0 + l`

`64"in" - 4y = l`

`l = 64"in" - 4y`