Question #f6259

1 Answer
Aug 14, 2017

"length" = 3x+2

Explanation:

The equation for the perimeter of a rectangle is

P = 2l + 2w

where

  • l is the length of the rectangle

  • w is the width of the rectangle

We're given:

  • P = color(red)(8x-4

  • w = color(green)(x-4

Plugging these in:

color(red)(8x-4) = 2l + 2(color(green)(x-4))

Simplifying:

8x-4 = 2l + 2x - 8

Now we solve for l:

Subtract 2x from both sides:

6x - 4 = 2l - 8

Add 8 to both sides:

6x+4 = 2l

Divide both sides by 2:

color(blue)(ulbar(|stackrel(" ")(" "l = 3x+2" ")|)

The length of the rectangle (in terms of x) is thus color(blue)(3x+2.