math
posted by meldrick on .
the length of a car park is 120 m. longer than its width the area of the car park is 6400 m(2) how would you represents its width

I would let the width = x
then the length is x+120
and
x(x+120) = 6400
x^2 + 120x  6400 = 0
which factors to
(x40)(x+ 160) = 0
x =40 or x = 160, which is not possible, can't have negative width
width is 40, length is 40+120 = 160
check: area = 40(160) = 6400 , yup!! 
the length of a car park is 120 in longer than its width the area of the car park is 6400m