In Exercises 13-15, find two different sets of parametric equations for the given rec- tangular equation. (There are many correct answers.) 13. y = x2 + 10 14. x + y = 4 15. x2 + 4y- - 16 = 0 16. Convert the polar coordinate ( - 14, 5 17 3 to rectangular form. 17. Convert the rectangular coordinate (2. -2) to polar form and find two additional polar representations of this point. (There are many correct answers.) 18. Convert the rectangular equation x2 + y2 - 12y = 0 to polar form. 19. Convert the polar equation r = 2 sin 0 to rectangular form. In Exercises 20-22, identify the conic represented by the polar equation algebraically. Then use a graphing utility to graph the polar equation. 4 20. r = 2 + 3 sin 0 21. r= 1 - cos 0 22. r= 2 + 3 sin 0 23. Find a polar equation of an ellipse with its focus at the pole, an eccentricity of e = 7, and directrix at y = 4. 24. Find a polar equation of a hyperbola with its focus at the pole, an eccentricity of e = 3, and directrix at y = 2. 25. For the polar equation r = 8 cos 30, find the maximum value of |r) and any zeros of r. Verify your answers numerically