9.
slove this question

Answer:
[tex]\sqrt{x^2 + y^2}[/tex]
Step-by-step explanation:
to find diatance between AB
A(0 , 0) = (x1 , y1)
B(x , y) = (x2 , y2)
distance formula = [tex]\sqrt{(x2 - x1)^2 + (y2 - y1)^2}[/tex]
=[tex]\sqrt{(x - 0)^2 + (y - 0)^2}[/tex]
=[tex]\sqrt{x^2 + y^2}[/tex]