The slope of one of the dotted lines is equal to: 1.
The slope of the reflection line is equal to: -1.
In Mathematics and Geometry, the slope of any straight line can be determined by using the following mathematical equation;
Slope (m) = (Change in y-axis, Δy)/(Change in x-axis, Δx)
Slope (m) = rise/run
By substituting the given data points (-5, 6) and (-2, 9) into the formula for the slope of a line, the slope of one of the dotted lines is given by;
Slope (m) = (9 - 6)/(-2 + 5)
Slope (m) = 3/3
Slope (m) = 1.
By substituting the given data points (-5, 6) and (-4, 5) into the formula for the slope of a line, the slope of the reflection line is given by;
Slope (m) = (5 - 6)/(-4 + 5)
Slope (m) = -1/1
Slope (m) = -1.