
Find the equations for the parabolas described below: (a) vertex is 2 units from the x-axis, opens downward, symmetric about x = 1, y-intercept = 23/12 (b) has vertical axis of symmetry and passing through (-2,3), (0,3), and (1,9). (c) Opens upward, passing through (-2,7), vertex is on the positive y-axis and is 5 units from the origin. (d) Find an equation that represents a parabola which opens to the right, has its vertex at (2,2) and passes through the point (5,0).
HINT:
The trick to these problems is to solve for the constant, C, and the coefficients, A and B. A good approach is to solve for C first, then create a system of equations that will allow you to solve A and B. (a) Remember Standard Form y = Ax2 + Bx + C. Use point (0, 23/12) to solve C. (h, k) = (-B/2A , C- (B2/4A))