The area of a rectangle is 42 square inches and one side is 12 inches long find the perimeter of the rectangle show your work

So first of all we need to know that area is length times width
Area = L x W 
since we know the area is 42 and the length is 12 lets plug those in
42 = 12 x W 
now we dont know what W is yet but we can figure it out by dividing 42 by 12
42/12 = 3.5 
So W = 3.5!
but its asking for the perimeter and we know that perimeter is all of the sides of the rectangle added up. Heres a picture
   
       ___3.5___
      |                 |
      |                 |
 12 |                 |  12 
      |                 |
     
             3.5

see now we just add those all up together:)

12 + 12 + 3.5 + 3.5 = 31!!
so our perimeter is 31 inches:)
have a good one 
PICK ME BRAINLIEST!:D

The answer is 49/16 or 3 1/16

Do you mean conversion factor?