1: How can you tell if the parabola opens upward or downward?
5: See the first slide for an illustration of each of these.
7: Calculate h ＝ -b divided by 2a, and then plug this value in as x to find k.
12: 2 times -3/4 is -6/4, and dividing by this is the same as multiplying by -4/6.
19: b is -12, not 12.
21: k is the minimum value if the parabola opens upward or the maximum value if the parabola opens downward.
31: Parabolas are symmetrical, so if you move the same distance to the right or to the left of the vertex, the new y value will be the same either way.
44: -b/2a is h, the x-coordinate of the vertex.