As an afterthought....maybe the patio does not include the pool area and hot tub area?
THEN the area becomes
the previous finding for the entire area MINUS the pool and hot tub areas
pool area = (6x-14)(2x) = 12x^2-28x
hot tub area = x * x = x^2
Subtract these from our previous area ( 32x^2-40x)
32x^2 - 40 x - (12x^2 -28x) - (x^2)
32x^2 - 12x^2 - x^2 - 40x + 28x = 19x^2 - 12x = 'patio' area w/out pool and hot tub areas
Then if x= 9 area =19*81-12*9 = 1431 and cost 1431sqft x $10/sqft =$14310