Answer:
13
Step-by-step explanation:
The distance that [tex]a+bi[/tex] has from [tex]0+0i[/tex] is:
[tex]\sqrt{(a-0)^2+(b-0)^2}[/tex]
[tex]\sqrt{a^2+b^2}[/tex]
So let's just apply the formula there:
[tex]\sqrt{(5)^2+(12)^2[/tex]
[tex]\sqrt{25+144}[/tex]
[tex]\sqrt{169}[/tex]
[tex]13[/tex]