There are two ways to do this. Either use the Polynomial graphing object as follows:
Click on the "+" at the top to select graphing objects to be used for the question.
You need to enter sufficient points given the degree of the polynomial, and then when you are done, click back on the first point that you entered, "A".
Example : y = x3
Then click back on point A:
You can also enter subtypes such as a line for which two points are needed:
But you can enter more points than the minimum, such as entering five points for a line:
However, note that in some cases the function solver may fail to determine the intended polynomial such as if the points provided for the function are not singly-valued, e.g.