SOLUTION: If the sides of a square are lengthened by 7 cm, and the area becomes 256 cm ^2. What is the length of a side of the original square?

Algebra ->  Length-and-distance -> SOLUTION: If the sides of a square are lengthened by 7 cm, and the area becomes 256 cm ^2. What is the length of a side of the original square?      Log On


   

Question 275219: If the sides of a square are lengthened by 7 cm, and the area becomes 256 cm ^2. What is the length of a side of the original square?
Answer by user_dude2008(1862) About Me  (Show Source):
You can put this solution on YOUR website!
(x+7)^2=256

x^2+14x+49=256

x^2+14x-207=0

(x-9)(x+23)=0

x=9 or x=-23

Answer: Original length is 9 cm