13_y=x2+10 l4.x+y2=4 15.x2+4y216=0 571' 16. Convert the polar coordinate ( l4, ?) to rectangular form. 17. Convert the rectangular coordinate (2, -2) to polar form and nd two additional polar representations of this point. (There are many correct answers.) 18. Convert the rectangular equation x2 + y2 12y = O to polar form. 19. Convert the polar equation r = 2 sin 6 to rectangular form. In Exercises 2022, identify the conic represented by the polar equation algebraically. Then use a graphing utility to graph the polar equation. . _ l = 4 20.r2+3$tn9 2Lr_lcos 22.r 2+3sin9 23. Find a polar equation of an ellipse with its focus at the pole. an eccentricity of e = 2'", and directrix at y = 4. 24. Find a polar equation of a hyperbola with its focus at the pole, an eccentricity of e = i, and directrix at y = 2. 25. For the polar equation r = 3 cos 39, nd the maximum value of |r| and any zeros of r. Verify your answers numerically