Question

kelly wants to create a rectangular playpen for his cats in his backyard, and estimates that the cats will need 500 square feet. he also wants the length of the playpen to be 20 feet longer than the width, so they have room to run. what dimensions should the playpen be?

Answer 1

Assuming that x = width 
the length would be = x+20

x (x+20) = 500
X^2 +20x - 500 = 0

Based on the equation above, you can find the x which will became the width and then added that width with 20 and you find the length

hope this helps