Question

The length of a rectangular field is 6 metres longer than its width. If the area of the field is 72 square metres, What are the width and the length of the field?

Answer 1

The length is 12metres, the width is 6metres

Explanation:

Suppose the width is x, the length is x+6

The square is 72. The square of rectangular field is equal to product of length and width.

so x(x+6)=72

x^2+6x-72=0

a=1 b=6 c=-72

D= b^2-4ac= 6*6+288= 36+288= 324

sqrtD= 18

x1= (-b-sqrtD)/2a=(-6-18)/2= -12 (it is negative, but width is only positive. So this root doesn't match)

x2=(-b+sqrtD)/2a= (-6+18)/2= 12/2=6 - the width

The length is 6+6=12