Convert the point to polar coordinates using the interval [0, 2\small \pi) for θ.
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First we need to find r
[tex]r=\sqrt[]{x^2+y^2}[/tex]in this case
x=0
y=-3
[tex]r=\sqrt[]{0^2+(-3)^2}=3[/tex]Because the x-coordinate is 0 and the y-coordinate is negative the angle is 270°=3/2pi
ANSWER
[tex]3\angle\frac{\text{3}}{2}\pi[/tex]