Two sides of a rectangular desktop are 3 feet long. The area of the desktop is 15 square feet. What's the perimeter of the desktop

First you need to find the other sode length of the desktop and because its a rectangle the two other sides will be equal. you know the area is 15 and to find area you multiply length and width so to get the other side dived 15 by 3 to get 5 and then do 3+3+5+5 which would give you the perimeter = 16