How do you find $abs(-1 - 2i)$ ?

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Answer 1 · 2016-03-29T20:27:03

$|-1-2i|=sqrt5$

Let $z=x+iy$ be any complex number in rectangular form.

Then the modulus may be given by $|z|=sqrt(x^2+y^2)$ .

So in this particular case we get:

$|-1-2i|=sqrt((-1)^2+(-2)^2)=sqrt5$ .

How do you find abs(-1 - 2i)abs(-1 - 2i)?