2. Use `h` ＝ 1, `k` ＝ 2, and any value of `a`.

3. Subtracting from `x` moves a graph to the right, and adding to the expression moves the graph upward.

31. The vertex is the point (`h`, `k`), and the axis of symmetry is the line `x` ＝ `h`.

35. Identify the vertex and the direction of the parabola.

37. How is this different from #36?

42. Identify the vertex, and sketch the parabola downward from there since the leading coefficient is negative.