Question 579237
Area of garden = 90 * 40 ft = 3600 sq. ft

1/3 of this area is cut = 1200 sq. ft

Let the uniform width be x
so the reduced length = 90-2x
reduced width = 40-2x

area of this portion is ( 90-2x)((40-2x)

Total area - reduced area = area of the grass cut

3600-(90-2x)(40-2x)= 1200
(90-2x)(40-2x)= 3600-1200
90(40-2x)-2x(40-2x) = 2400
3600-180x-80x+4x^2=2400
4x^2-260x+1200=0
/4
x^2-65x+300=0

x^2-60x-5x+300=0

x(x-60)-5(x-60)=0
(x-60)(x-5)=0
x= 60 not possible
x= 5 ft the width 

m.ananth@hotmail.ca