The perimeter of a parallelogram is 48 inches.What is the length of the longer side if the shorter side measures 9 inches?

Question

Please help. This is on my review packet and I don't quite understand it.

Answer 1

First, draw a parallelogram and label the sides with the dimensions L, S=9, L, and S=9.  [note:  opposite sides of a parallelogram are of equal lengths]

 

The problem statement tells us the value of P [the distance around] = perimeter = 48 = L + 9 + L + 9.

 

   48 = 2L + 18

   30 = 2L         [subtract 18 from both sides]

   15 = L          [divide both sides by 2]

 

Check:  If L=15 and S=9, what is P?

  P = 15 + 9 + 15 + 9

  P = 48     [that checks!]