Final answer:
The slope of the line passing through the points (4,9) and (5,5) is calculated using the slope formula (y2 - y1) / (x2 - x1), which results in a slope of -4.
Step-by-step explanation:
To find the slope of the line that goes through the pair of points (4,9) and (5,5), we can use the slope formula which is (y2 - y1) / (x2 - x1). The slope, often represented as 'm', can be calculated by taking the difference in the y-values divided by the difference in the x-values.
Using the points given: (4,9) and (5,5), we have:
m = (5 - 9) / (5 - 4)
m = (-4) / (1)
m = -4
Therefore, the slope of the line that goes through points (4,9) and (5,5) is -4.