Question

What is true about the complex number -5 - 5i? A. The modulus is 5√2. B. It lies in quadrant 3. C. The modulus is 5. D. It lies in quadrant 2.

Answer 1

Answer:

A. The modulus is 5√2.

B. It lies in quadrant 3

Step-by-step explanation:

Given a complex value z = x = iy

The modulus is expressed as;

|z| = √x²+y²

Given the complex number z = -5 - 5i

|z| = √(-5)²+(-5)²

|z| = √25+25

|z| = √50

|z| = √25 * √2

|z| = 5√2

For the argument;

theta = arctan(-5/-5)

theta = arctan 1

theta = 45degrees

since tan is positive in the third quadrant, hence it lies in quadrant 3