= = 13.21 (Algebra: vertex form equations) The equation of a parabola can be expressed in either standard form (y ax + bx + c) or vertex form (y = a(x h) + k). Write a program that prompts the user to enter a, b, and c as integers in standard -b form and displays h = and k 2a 4ac-621 4a in the vertex form. Display h and k as rational numbers. Here are some sample runs: Enter a, b, c: 1 3 1 Enter h is -3/2 k is -5/4 Enter a, b, c: 2 3 4 Enter h is -3/4 k is 23/8