(a) Find out roots of the equation: x2 - 2x - 3 = 0.
(b) Find out vertex of parabola y = x2 - 2x - 3.
(c) Use parts a and b to draw graph of y = x2 - 2x - 3. You may want to find out the few other "points that parabola passes through" to get more accurate graph.