The next page contains exercises to give you some practice sliding and stretching curves or doing both. For each exercise, the idea is to get the curve to appear on your screen. Pay close attention to the places where the curves intersect the axes. You may want to zoom in or out to make sure it's really the same curve (though your window may be a different size from the one on the page). You can even use n to help you find the parameters you want.
Here is an example. Suppose you wanted to find the equation that made the curve above. How would you go about finding it? Here's one way; at first you may do a lot of experimentation between each of these frames.
| Start with a "basic" curve, in this case, y = x2. |
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First we adjust the shape. The target curve goes through (1, 0), which is over 2 and up 2 from (1, 2), its vertex. The basic curve goes up 4 when it goes over 2, so we compress the curve by a factor of 2 in the y-direction. |
 | Next, the vertex has to move 1 to the left, so add 1 to every x. |
 | Finally, the vertex has to go down 2, so we subtract 2 from the whole expression. Now the vertex is at (1, 2), where it belongs. |
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