Answer:
Let us say x is a real number and z = a + ib is complex
|x| > 0
|z| = |a + ib| = square-root (a^2 + b^2)
Explanation:
|x| > 0 the absolute value of a real number is a nonnegative real number
The |a + ib| = square-root of the sum of the squares of the real components of the complex number