convert the rectangular equation to polar form.Assume a > 0x=18
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To convert a rectangular equation to polar forma, we use
[tex]x=r\cos (\theta),y=r\sin (\theta)[/tex]In the equation x=18, we only have x, so
[tex]\begin{gathered} 18=r\cos (\theta) \\ r=\frac{18}{\cos(\theta)}=18\sec (\theta) \end{gathered}[/tex]