SOLUTION: This is a problem to determine the width and length of a rectangle where the length is 45 feet more than the width. The area is 9000 feet. What formula is used to determined the w

Algebra ->  Quadratic Equations and Parabolas  -> Quadratic Equation Customizable Word Problems -> SOLUTION: This is a problem to determine the width and length of a rectangle where the length is 45 feet more than the width. The area is 9000 feet. What formula is used to determined the w      Log On


   

Question 860473: This is a problem to determine the width and length of a rectangle where the length is 45 feet more than the width. The area is 9000 feet. What formula is used to determined the width and length. We tried and tried to figure out, but can't do it. Please help
Answer by mananth(16946) About Me  (Show Source):
You can put this solution on YOUR website!
width = x
length = x+45

Area = L * W
Area = x(x+45)
x(x+45)=9000
x^2+45x=9000
x^2+45x-9000=0
x^2+120x-75x-9000=0
x(x+120)-75(x+120)=0
(x+120)(x-75)=0
x= -120, x=75
width = 75 feet
length = 75+45=120 feet