Question 1131216
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Convert the polar equation to rectangular coordinates. (Use variables x and y as needed.)
r = −3
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Traditionally, in polar coordinates, the variable " r " is the distance from the origin in a coordinate plane.


In polar coordinates, the radius r should be non-negative to describe non-empty set of points.


In your case, with r negative  r= -3, it describes EMPTY set of points.
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The answer by @MathLover1 is incorrect.