1. Quadratic equations have the highest degree of 2. Therefore, the maximum amount of solutions can be 2 or unreal. The graphs with 2 solutions would cross over the x-axis twice, 1 solution would touch the x-axis once and 0 solutions would not touch the x-axis.
2. Find x and y intercepts of the equation. Calculate points at a constant intervals and plot points on graphing paper. Connect the points.
3. Following the movement of a ball through air? <-- not sure about this one
Hope I helped :)
