Cubic Graphs have i done them correctly

Yes that's correct

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Woo! Thanks

Close.

In your second graph, it is important the the curve goes through the roots, yours goes underneath them.

And when they go off to infinity, the curve just gets steeper, it does not start to become shallower as you have for x from 2 to 5 in the first graph, and from x=4 in the second.

Here's the actual first graph:

Actually no, in your second graph the curve needs to go through (-1,0), (0,0) and (4,0). Between (-1,0) and (0,0) the value of y should be positive . So it goes up and then down.

Oh so the second one has to go slightly above the x axis?

Like this instead?

Yes.

But you also want to take care of the curvature at the ends.