a. We can see that this parabola opens downward, as in this example,
b. The axis of symmetry equation of a parabola whose vertex is (h, k) and opens up/down is: x = h. Therefore, the equation is x = 1
c. The vertex of a parabola is the point at the intersection of the parabola and its line of symmetry. In this case, it is (1,9)
d. Intercepts,
The x -intercepts are the points at which the parabola crosses the x -axis. If they exist, the x -intercepts represent the zeros, or roots, of the quadratic function, the values of x at which y=0 .
Therefore, x-intercepts: -2,4
The y -intercept is the point at which the parabola crosses the y -axis.
Therefore, y-intercept: 8
