Question 126361
If the lengths of the sides are consecutive even integers, then you can say that the longer one is x and the shorter one is x - 2.


The perimeter of a parallelogram is just the sum of the 4 sides.  Here we have 2 sides of length x and 2 sides of length x - 2, so adding them all up:


{{{x + x + (x - 2) + (x - 2)=36}}}


{{{4x-4=36}}}


{{{4x=40}}}


{{{x=10}}}.  So the longer side measures 10 cm.


Check:

If the longer side is 10 cm, then the shorter side must be 8 cm.  2 times 8 is 16, 2 times 10 is 20, and 16 plus 20 is 36, answer checks.