Final answer:
The y-intercept in the equation y = mx + b is represented by the term b; it indicates the point where the line crosses the y-axis. To determine the y-intercept, simply look at the value of b in the equation, which reveals where on the y-axis the plot line begins.
Step-by-step explanation:
To find the y-intercept of the linear equation y = mx + b, we look at the value of b as it represents the y-intercept in the slope-intercept form of a linear equation. The y-intercept is the point where the line crosses the y-axis, which occurs when the x-value is zero. Therefore, in the equation y = mx + b, the y-intercept occurs at the point (0, b), indicating that the line begins on the y-axis at the value of b.
For instance, if we have a line with the equation y = 3x + 9, the y-intercept is 9 because when x=0, y will equal 9, showing the line crosses the y-axis at (0, 9). The slope, represented by m, defines the steepness of the line, calculated as the rise over the run. Specifying both a y-intercept and a slope creates a visualization of a specific line on a graph.