Answer:
Cindy uhh, I can't really see the figures well but I think you'll insert the x and y values into the function given and solve for A, B and C simultaneously.
where you see f(x), put in there the y value of the point and where you see x , put in the x value of the point.
Also ,you can nullify A and B to get C first . You can do that by putting zero in place of x and putting it's correspondent on the y axis into f(x)