Question

what is true about the complex number -5-5i
a. the modulus is 5 sqrt2
b. it lies in quadrant 2
c. the modulus is 5
d. it lies in quadrant 3

Answer 1

Think of that number as just a vector in the complex plane.
If your complex number is a+bi
modulus = sqrt(a^2 + b^2)
To find the quadrant, draw it and check.

Answer 2

i think it lies in quadrant 3 and not quadrant 2

Answer 3

for the modulus is it 5?

Answer 4

It is in quadrant 3 but modulus is not 5
modulus = sqrt(a^2+b^2)=sqrt((-5)^2+(-5)^2)=sqrt(25+25)= sqrt(50) = sqrt(2*25)=5sqrt(2)

Answer 5

oh I see my mistake. Thank you :)