SOLUTION: Ahmad wants to create a rectangular garden in a backyard. He wants it to have a total area of 120 square feet, and it should be 12 feet longer than its wide. By using completing th

Algebra ->  Customizable Word Problem Solvers  -> Misc -> SOLUTION: Ahmad wants to create a rectangular garden in a backyard. He wants it to have a total area of 120 square feet, and it should be 12 feet longer than its wide. By using completing th      Log On

Ad: Over 600 Algebra Word Problems at edhelper.com


    

Question 902585: Ahmad wants to create a rectangular garden in a backyard. He wants it to have a total area of 120 square feet, and it should be 12 feet longer than its wide. By using completing the square method, what dimensions should he use for the garden? Give your answer in 3 significant figures.
Answer by Jc0110(165) About Me  (Show Source):
You can put this solution on YOUR website!
Let width = x.
Length = 12 + width
Length = 12 + x
width x length = area of rectangular garden
X x (12 + x) = 120
12x + x%5E2 = 120

Completing the square:
... Take note that the whole "PLUS_MINNUS-" is actually . Sorry because I can't type into the equation.
x%2B6=sqrt%28156%29 or x%2B6=-sqrt%28156%29
x=sqrt%28156%29-6 or x=-sqrt%28156%29-6
x=6.49 or x=-18.5
x=6.49 is acceptable, while x=-18.5 is unacceptable since dimensions of an object cannot be in negative.

Dimensions of the rectangular garden:
Width = x = 6.49 ft
Length = 12 + x
Length = 12 + 6.49
Length = 18.49 ft