Respuesta :

Answer:

[tex]4-i[/tex]

Step-by-step explanation:

The distance of a complex number

[tex]z=a+bi[/tex]

from the origin is given by:

[tex]|z|=\sqrt{(a-0)^2+(b-0)^2}[/tex]

[tex]|z|=\sqrt{a^2+b^2}[/tex]

The length of  [tex]2+15i[/tex] is;

[tex]=\sqrt{2^2+15^2}[/tex]

[tex]=\sqrt{4+225}[/tex]

[tex]=\sqrt{229}[/tex]

The length of  [tex]17+i[/tex] is;

[tex]=\sqrt{17^2+1^2}[/tex]

[tex]=\sqrt{289+1}[/tex]

[tex]=\sqrt{290}[/tex]

The length of  [tex]20-3i[/tex] is;

[tex]=\sqrt{20^2+3^2}[/tex]

[tex]=\sqrt{400+9}[/tex]

[tex]=\sqrt{409}[/tex]

The length of  [tex]4-i[/tex] is;

[tex]=\sqrt{4^2+1^2}[/tex]

[tex]=\sqrt{16+1}[/tex]

[tex]=\sqrt{17}[/tex]

The correct choice is D

Its "4 - i"... i just took the test