A 22-ft by 28-ft rectangular swimming pool is surrounded by a walkway of uniform width. If the total area of the walkway is 336 ft2, how wide is the walkway?

1) we calculate the area of the swimmning pool

area of this swimming pool = (22ft) (28 ftt) = 616 ft².

2) we calculte the total area of the swimming pool + area of the walkway

Total area=area of the swimming pool + area of the wakway

Total area=616 ft²+336 ft²=952 ft².

3) we can suggest this equation:

x=width

(22+2x) (28+2x) = 952

616+44x+56x+4x²=952

4x²+100x-336=0

x²+25x-84=0

x=[-25⁺₋√ (625+366) ]/2 = (-25⁺₋31) / 2

we have two solutions:

x₁ = (-25-31) / 2=-28 this solution is not valid.

x₂ = (-25+31) / 2=3

Answer: the width of the walkway is 3 ft.