help me please

Question

Mr. Brown just fenced in an area for his dog. He used exactly 40 feet of fencing for the rectangular shaped enclosure. If the length of the enclosure is 14 feet, what is its width? The formula for the perimeter of a rectangle is P = 2l + 2w.

Answer 1

Here's what we know:

P = 2L + 2w

P = 40 (the perimeter is 40 ft)

L = 14 (length is 14 ft)

 

We have values for some of our variables, so let's plug them in:

40 = 2 * 14 + 2w

40 = 28 + 2w

Subtract 28:

12 = 2w

 

I'm sure you can isolate w from here.