Answer:
B
Step-by-step explanation:
We want to find the value of:
[tex]\displaystyle |6-3i|[/tex]
Recall that given a complex number z in the form:
[tex]z=a+bi[/tex]
The absolute value of z will be given by:
[tex]\displaystyle |z| = \sqrt{a^2+b^2}[/tex]
We have the complex number:
[tex]6-3i[/tex]
Thus, a = 6 and b = -3.
Then its absolute value will be:
[tex]|6-3i|=\sqrt{(6)^2+(-3)^2}[/tex]
Evaluate:
[tex]\displaystyle |6-3i|= \sqrt{36+9}=\sqrt{45}=3\sqrt{5}[/tex]
Hence, our answer is B.
