The form of quadratic is:
Since (0,6) is given, we know c = 6, thus we have:
Point 2 is (2,8), replace x and y and find equation:
Putting point 2 (3,0), we have:
Solving the 2 simulatenous equations for a and b, we get:
a = -3
b = 7
Now u have all the values, a, b, and c.
Just put it in the general form of parabola :
y = -3x^2 + 7x + 6