Final answer:
The question requires analysis of a function's positive value and decreasing positive slope at x=3. None of the given options, y=13x or y=x², completely satisfy these conditions as the first has a constant slope and the latter has an increasing slope with increasing x.
Step-by-step explanation:
The question pertains to the analysis of the function f(x) at a particular value of x, where the function has a positive value and a positive but decreasing slope. Based on the given options, we can eliminate the linear function y=13x, as its slope is constant and positive, not decreasing.
Considering the option y=x², at x=3, f(3)=9, which is positive. The slope of the function (represented by the derivative) is 2x, so at x=3, the slope is 2(3)=6, which is also positive. Furthermore, as x increases, the magnitude of the slope also increases, not decreases.
Therefore, neither of these options fully matches the conditions described in the question. The graph of a function is often created by plotting specific x, y data pairs, and optionally, the characteristics of the derivative of the function can be analyzed to understand the nature of the slope at given points.