For the following functions: 0 = 500x^2 + 30x – 200 0 = 20x^2 + 13x + 15 0= 15x^2 -25x – 25 what are their discriminates? (b) what is the significance of these discriminates? complete the square and thereby solve for x for these equations ( do this both by hand and using the excel solver, see excel instructions below). (d) use excel to graph of these functions. to use the solver: (a) • construct the formula for the equation 0 = 500x2 + 30x - 200; in b1 sum (c1: e1), c1 =500*c2a2, d1 = 30*c2, e1 = -200, c2 the starting value for x. • go to solver (tools or formula), set cell $b$1, equal to 0, by changing c2, solve. • keep trying different starting values of x until you have found all solutions. • if you have trouble go to . (2 marks)