How do you convert $x^2 – 9 = 0$ into polar form?

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Answer 1 · 2015-11-27T19:03:58

$r^2 = 9cos^2(theta)$

Since $r=xcos(theta)$ , you have that $x=r/cos(theta)$ . Take the square and substitute, and you'll get

$r^2/cos^2(theta) - 9=0$

which you can rewrite as

$r^2 = 9cos^2(theta)$

How do you convert x^2 – 9 = 0x^2 – 9 = 0 into polar form?