See Exercise 9.15 in the Chapter 9 Programming Exercise from the Book section for the description of this exercise.

Sample Run
Enter the real part of the first complex number: 3.5
Enter the imaginary part of the first complex number: 6.5
Enter the real part of the first complex number: -3.5
Enter the imaginary part of the first complex number: 1
(3.5 + 6.5i) + (-3.5 + 1i) = (0.0 + 7.5i)
(3.5 + 6.5i) - (-3.5 + 1i) = (7.0 + 5.5i)
(3.5 + 6.5i) * (-3.5 + 1i) = (-18.75 - 19.25i)
(3.5 + 6.5i) / (-3.5 + 1i) = (-0.43396226415 - 1.98113207547i)
|(3.5 + 6.5i)| = 4.47213595499958.
In Python.