Focus and DirectrixYou only need to do 6 problems Do 7, 8 , 9 , 14, 16, 19, 21 Writing and interpreting Quadratics when using Focus and Directrix.

7. Which of the given characteristics describe parabolas that open up? Explain your reasoning. A. focus: (0, 3) B. focus: (0, -5) C. focus: (0, -10) directrix: y = -3 directrix: y = 5 directrix: y = 10 In Exercises 8-10, identify the focus, directrix, and axis of symmetry of the parabola. Graph the equation. 8. y = 12X2 9. ) = x2 16 10. x = 11. The cross section (with units in inches) of a parabolic satellite dish can be modeled by the equation p Thex2. How far is the receiver from the vertex of the cross section? Explain. In Exercises 12-17, write an equation of the parabola with the given characteristics. 12. focus: (2, 0) 13. focus: (-4, 0) 14. focus: (0. ) directrix: x - -2 directrix: x = 4 directrix: V - 15. directrix: x = -6 16. focus: (0. 2) 17. directrix: x = 1 vertex: (0. 0) vertex: (0, 0) vertex: (0. 0) In Exercises 18-21, identify the vertex, focus, directrix, and axis of symmetry of the parabola. Describe the transformations of the graph of the standard equation with p - 1 and vertex (0, 0). 18. = 17( X - 1) + 3 19. 8 ( x + 5) - 2 20. T - -(7 + 4) + 2 28 ( X + 6)+ 10