Question

The formula for the perimeter of a rectangle is p=2l+2w, where l is the length and w is the width. A rectangle has a perimeter of 24 inches. Find its dimensions if its length is 3 inches greater than its width.

Answer 1

Hello!

Let's put this as a system of equations.

24=2l+2w

l=w+3

Let's plug this l value into the first equation.

24=2(w+3)+2w

24=2w+6+2w

24=4w+6

Now we subtract 6 from both sides.

18=4w

Divide both sides by 4.

w=4.5

Now we just add 3 to find length.

L=7.5

Note that these numbers to work in our original equation.

Width: 4.5 inches

Length: 7.5 inches

I hope this helps!

Answer 2

24=2(3+w)+2w

24=6+2w+2w

18=4w

4.5=w

24=2l+2(4.5)

24=2l+9

15=2l

7.5=l