Chapter 10 - Conics, Parametric Equations, and Polar Coordinates - 10.4 Exercises - Page 723: 89

$$x = - 1$$

$$\eqalign{ & r = - \sec \theta \cr & {\text{Rewrite trigonometric identities}} \cr & r = - \frac{1}{{\cos \theta }} \cr & r\cos \theta = - 1 \cr & {\text{Convert to rectangular form, using }}y = r\sin \theta ,{\text{ }}x = r\cos \theta \cr & x = - 1 \cr & {\text{Vertical line}} \cr & {\text{Graph}} \cr} $$