ANSWER
D) 9/2
Step-by-step explanation
Function f(x) is a linear function, whose equation is given in slope-intercept form,
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Where m is the slope and b is the y-intercept. In other words, the slope is the constant that multiplies x, in this case, 9/2.
Hence, the slope of the graph of y = f(x) in the xy-plane is 9/2.