If x = t, y = 2t, and y ≠ f(x), how to graph these equations?
Plot a point for every t.
Alternatively, calculate y=f(x).
Your condition y ≠ f(x) doesn't make sense. The definitions you give for x and y imply y = 2x, which is easily graphed.
In this case, y is ≠ f(x).
Possibly what you mean to say is that no function has been given for y in terms of x.
In some cases it is true that no function exists for y in terms of x. This would be because there are some values of x that pair up with more than one value for y. However, in the case at hand, it is trivial to find an f() such that y = f(x).
f(x) = 2x. What does your assertion mean?
Maybe he meant for y ≠ t?
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