The graph of the function f(x)-25- x2 is pictured to the right. Use this function to complete exercises 9-11. 9. Find the values of f(3) and (3). 4- 10. Find the equation of the line tangent to the graph of f(x) when x=3 and graph this line on the grid with f(x). 11. Find the equation of the normal line to the graph of f(x) when x=3 and graph this line on the grid with f(x). 12. At what value(s) of x does the graph of (x)=x2x+1 have a horizontal tangent? Show your work and give a reason for your answer.