Answer: Minimum; -3
Explanation:
I found the answer by entering it into Desmos Graphing Calculator and then looking at the point of the vertex, which in this case would be (9,-3).
You could also find the x-intercepts, (p,0) and (q,0), using the quadratic formula and then plug them into the equation: x=p+q/2 which will give you your axis of symmetry, or your x value in your vertex. Then, plug that number into your equation. You can plug it into the equation you posted here or the equation of your x-intercepts. (x-p) (x-q) Keep in mind that the minus refers to you putting the opposite of your x-intercept. For example, if your x-intercept was 4, then you would have -4 in the equation.