Consider the following parametric equations. a. Eliminate the parameter to obtain an equation in x and y. b. Describe the curve and indicate the positive orientation. x=r-5, y=r-9, -4 srs4 a. Eliminate the parameter to obtain an equation in x and y. y=x3+15x2+75x+116 (Type an equation.) b. Describe the curve and indicate the positive orientation. (Type ordered pairs. Simplify your answers.) OA. A cubic curve falls to the left as r increases, starting at and ending at 4 and ending at B. A cubic curve rises to the right as r increases, starting at -4 and ending at 4 OC. A quadratic curve falls and then rises to the left as r increases, starting at D. A quadratic curve falls and then rises to the right as r increases, starting at and ending at