Final answer:
The algebra of straight lines involves the equation y = mx + b, where 'm' is the slope, indicating the vertical change per unit of horizontal change, and 'b' is the y-intercept, where the line crosses the y-axis.
Step-by-step explanation:
The question relates to the algebra of straight lines, specifically focusing on the equations that represent non-vertical straight lines in a plane: y = mx + b, where m is the slope, and b is the y-intercept. In the context of these equations, 'm' represents the ratio of the vertical change (rise) to the horizontal change (run) between any two points on the line. 'b' represents the exact point on the y-axis where the line intersects when x is zero. For example, if a line has an equation y = 3x + 9, the slope (m) is 3, indicating a rise of 3 units for every 1 unit increase along the x-axis, and the y-intercept (b) is 9, indicating that the line intersects the y-axis at the point (0, 9).