Respuesta :
A complex numbers [tex]z = a+bi[/tex] has a magnitude [tex]|z|=\sqrt{a^2+b^2}[/tex].
Then notice for D, [tex]z = 4-i[/tex] implies [tex]a = 4, b=-1[/tex] so [tex]|z| = \sqrt{4^2+(-1)^2} = \sqrt{16+1}=\sqrt{17}[/tex]
Then notice for D, [tex]z = 4-i[/tex] implies [tex]a = 4, b=-1[/tex] so [tex]|z| = \sqrt{4^2+(-1)^2} = \sqrt{16+1}=\sqrt{17}[/tex]
