You know point A is (0,8)
Substitute x = 0, y = 8, into the equation of the graph, y = (x+p)(2-x) and solve for p. Once you have p, you can solve the rest.
Now that you have the equation, do you know how to find the roots of an equation? To make y = 0?
If x = 2, y = 0. This one is given for you, it's point c.
If x = ..., y = 0. This one you can solve yourself.
Solve the second root and that's the x-coordinates for b.
Oh, I see, so I'll take as , hence-
or
or
Now, since the value must be negative at the point ,
I should reject and take as the answer.
Also, the value at point must be .
Hence B is (-4,0).
Now I would have to do part (c).
The line of symmetry is the midpoint of the parabola.
What am I suppose to do now?