Answer:
[tex]\sqrt{p^2+q^2}[/tex]
Step-by-step explanation:
The distance between two points [tex](x_1,y_1)[/tex] and [tex](x_2,y_2)[/tex] can be calculated as
[tex]\sqrt{(x_1-x_2)^2+(y_1-y_2)^2}.[/tex]
Then the distance between points [tex](p,q)[/tex] and [tex](0,0)[/tex] is
[tex]\sqrt{(p-0)^2+(q-0)^2}=\sqrt{p^2+q^2}.[/tex]
