Step 1: Find the slope:
Step 2: Set up your equation 
using one of the points.
Using (5,6) we have 
.
Using (6,10) we have 
Both of those equations would be correct.
Answer:
4.2
Step-by-step explanation:
3.5 x 1.2 = 4.2
The roller coaster could be represented by the function for Choice D.
If you were to graph this function, you would find that the zeros (x-intercepts) of the function are at the points of -2 and 1. Those are the needed points in the problem.
Since this is a parabola that opens upward, the parabola must be below the axis (or support bar) between those values.
