Answer: Y=-(X-8)^2+6
Step-by-step explanation: Although I am not completely sure how to reflect over the x-axis, I believe this is the answer you are looking for.
Start with the basic vertex form equation: Y=a(x-h)^2+k
H will shift it to the left and right and k will shift it up and down.
I believe that reflecting over the x-axis had a different meaning than you intend as it would counteract the prior shifts.
A -1 value will flip the parabola leaving you with the above equation.