Is anyone able to do this word problem

How wide a strip must be mowed around a rectangular grass plot 40.0m by 60.0m for one half of the grass to be mowed?

x = border width
(60-2x)(40-2x) = 60*40/2 = 1200
2400-200x+4x^2=1200
4x^2-200x+1200=0
x^2-50x+300 = 0 use the quadratic formula
x = 6.972 m

Just map out the grass plot on a piece of a paper

Imagine a smaller rectangle with in the grass plot (which is the grass not cut)
to get the length of the sides of the smaller rectangle simply divide 40 and 60 by 2

40/2 = 20
60/2 = 30

But, the stripe around it must have the same width all around.
calculate the distances from the sides of the small rectangle to the big rectangle
40 - 20 = 20
10/2 = 10

60 - 30 = 30
30/2 = 15

Get an average distance between these lengths:

15 + 10 = 25
25/2 = 12.5

Width of strip = 12.5 m

let x be the width of the strip
so clearly area
=2(x*60 +(4-2x)*x){used 40-2x as the area of the four squares has already been counted }
other way
2(60*x{area of strip 1}+40*x{area of strip 2}-(4x^2){area of the 4squares on the corners ,as these have been counted twice }
so clearly
we get 4x^2-200x+1200=0
just solve the eq.(m getting about 6.97m)
hope it helps..

The area of the strip is Sₐ = (40.0 m • 60.0 m)/2.

Call the width of the strip s.

The length of the strip is 2((40.0 m - s) + (60.0 - s)) ∴

s = (40 • 60)/2 ÷ 2(40 - s + 60 - s)

s = (2400)/2 ÷ 2(100 - 2s)

s = 300/(50 - s)

(50 - s)s = 300

50s - s² = 300

s² - 50s + 300 = 0

s = (50 ± √(50² - 4 • 300))/2 (quadratic equation)

s = (50 ± √(2500 - 1200))/2

s = (50 ± √1300)/2

s = (50 ± 36.056)/2

s = 86.056/2 or 13.944/2

s = 6.972 meters.

The first zero is ruled out because the strip would be wider than the plot.