Final answer:
If Otisha increases her design fee to $25, the y-intercept of her graph will change because it represents the initial charge before any work is done. This modification shifts the starting point on the y-axis upwards, without affecting the slope, the domain of the function, or the x-intercept.
Step-by-step explanation:
If Otisha decides to increase her design fee to $25, the value that would change on her graph is the y-intercept. The y-intercept is the initial amount that Otisha charges before any work is done, which in her case is represented on the graph as the point where the line intersects the y-axis when x is 0. When the design fee is increased to $25, this means that the starting point on the y-axis shifts from its original value to $25. This change does not affect the slope of the line, which is determined by the rate she charges per hour of work, nor does it change the domain of the function, which represents all possible values of x, or the x-intercept, which is the value of x when y is 0.
Therefore, increasing the y-intercept causes the line to move vertically upward on the graph, without changing the line's slope, as described in the reference that states: "Increasing the y-intercept will cause the line to move horizontally right on the graph without changing the line's slope." The other options provided, such as the slope (C), domain of the function (D), or x-intercept (A), will remain the same when the y-intercept is modified.