How do you write the rectangular equations for $r = 4$ $r=4$ ?

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Answer 1 · 2016-01-01T00:31:30

$x^{2} + y^{2} = 16$ $x^2+y^2=16$

$r = \sqrt{x^{2} + y^{2}}$ $r = sqrt(x^2+y^2)$

So $r = 4$ $r = 4$ becomes $\sqrt{x^{2} + y^{2}} = 4$ $sqrt(x^2+y^2) = 4$

Square both sides to get:

$x^{2} + y^{2} = 16$ $x^2+y^2 =16$

How do you write the rectangular equations for r=4r=4 r=4?