Final answer:
A steady steep diagonal line on a graph usually indicates a linear relationship between two variables, described by the equation y = mx + b, where 'm' is the slope and 'b' is the y-intercept.
Step-by-step explanation:
A steady steep diagonal line starting from one point and ending at another on a graph with perpendicular axes usually represents a linear relationship between two variables, with the horizontal axis typically being the independent variable and the vertical axis the dependent variable. Such a graph takes the form y = mx + b, where 'm' represents the slope of the line, indicating the rate of change of the dependent variable in relation to the independent variable, and 'b' represents the y-intercept, or the point where the line crosses the y-axis, signifying the value of the dependent variable when the independent variable is zero.
When the slope 'm' is positive, as is the case for a steep diagonal line that rises from left to right, the relationship shown is a direct relationship, meaning that as the independent variable increases, so does the dependent variable. Conversely, if the slope were negative, the line would fall from left to right, and the relationship would be an inverse one.