Given that,
The area of a rectangular dining table = 9000 sq ft
Solution,
Let the width is b ft. Length is 20 less then four time the width.
Length = (4b-20) ft
The formula for the area of a rectangle is given by :
A = lb
Substitute all the values,
[tex]9000=b(4b-20)\\\\4b^2-20b-9000=0\\\\\text{It is a quadratic equation, when we solve it we get :}\\\\b=50,-45\ feet[/tex]
Neglecting negative value, b = 50 ft
Length, l = (4(50)-20)
l = 180 ft
So, the length is 180 ft and width is 50 ft.
