Final answer:
The slope of the line passing through the points (9,1) and (10,-1) is -2.
Step-by-step explanation:
The slope of a line passing through two points can be found using the formula:
slope = (change in y)/(change in x)
Using the given points (9,1) and (10,-1), we can calculate the slope as:
slope = (-1 - 1)/(10 - 9) = -2/1 = -2
Therefore, the slope of the line passing through the points (9,1) and (10,-1) is -2.