Homework Write the standard form of the equation of each circle described. Then graph the equation. 15. center at (0, 0), radius 5 16. center at (-4, 7), radius V3 17. center at (-1, -3), radius V2 2 18. center at (-5, 0), radius , 19. center at (6, 1), tangent to 20. center at (3, -2), tangent to y = 2 the y-axis Write the standard form of each equation. Then graph the equation. 21. 36 - x2 = y2 22. x2 + 12 + y = 23. x2 + 2 - 4x + 12y + 30 = 0 24. 2x2 + 2y2 + 2x - 4y = -1 25. 6x2 - 12x + 6)2 + 36y = 36 26. 16x2 + 16y2 - 8x - 32y = 127 27. Write x2 + 32 + 14x + 24y + 157 = 0 in standard form. Then graph the equation