Final answer:
When m=0 in a linear function, the function is a constant and takes the form f(x) = b, where b is the y-intercept and represents the maximum value on the y-axis.
Step-by-step explanation:
When m=0 in a linear function, the function takes the form of f(x) = b, where b is the y-intercept of the graph of the equation. In general, a linear equation is expressed as y = mx + b, where m represents the slope and b represents the y-intercept. Since m is zero, the equation simplifies to y = b. This indicates that regardless of the value of x, the function will always have the constant value b, resulting in a horizontal line on the graph.
Graphically, the y-intercept is the value of y when x equals zero. This is the point where the line crosses the y-axis. Since this question specifies that f(x) equals the maximum value on the y-axis when x = 0, we can say that f(x) = b = m, the maximum y-value or y-intercept.