Final answer:
The slope of a mixed cost line in a regression analysis output from Excel is represented by the coefficient of the independent variable, labeled as 'b1' in the regression equation, indicating the change in the dependent variable for each unit change in the independent variable.
Step-by-step explanation:
In a regression analysis output generated with Excel, the slope of a mixed cost line is represented by the coefficient of the independent variable in the regression equation. For a linear regression, this is typically labeled with the variable b in the equation of the form ŷ = b0 + b1*x, where ŷ is the estimated value of the dependent variable, b0 is the y-intercept, and b1 is the slope. The slope indicates how much the dependent variable changes for a one-unit increase in the independent variable.
For example, in the regression equation ŷ = 173.51 + 4.83x, the slope is 4.83, meaning for every one unit increase in x (the independent variable), y (the dependent variable) is expected to increase by 4.83 units, on average. This interpretation is essential understanding how variables are correlated in regression analysis.