Question

Find the absolute value of the complex number 5 - 4i.

a.
-6.4
c.
6.04
b.
6
d.
6.4


Please select the best answer from the choices provided

Last question giving 50 easy POINTS!

Answer 1

I answered a similar question for someone else. The absolute value of a complex number is called the modulus. This represents the DISTANCE to the origin from the point on the imaginary + real plane.
the real horizontal distance is 5 and the imaginary vertical distance is in this case 4 (from -4i) the distance is 4. So to figure out this just use the Pythagorean theorem.
5^2 + (4)^2 = c^2
25 +16 = c^2
c^2 = 41c = 6.4 So option D.