The figure shows the graph of the quadratic function f(x) passing through the points A, B and C.
Write down the function f(x).
Compute the coordinates of the vertex of the function f(x).
At exactly how many points does the graph of the function f(x) and the line with the equation 
intersect?
Find all values of the parameter 
for which the graph of the function f(x) and the line with the equation 
intersect at two distinct points.
