Note: To determnine delta, you must zoom in a couple of times to see that delta = 0.005 makes the function y = |f(x) - 19| - 0.1 less than 0. The epsilon is then changed to 0.01; after one zooms in, you can see that delta = 0.0005 makes the function y = |f(x) - 19| - 0.01 less than 0. To change the value of epsilon, you must highlight with the mouse the number at the right of the delta or epsilon. To do this, you move the cursor to the number, press down the left mouse button and move across the number. After releasing the left mouse button you can then type the new value for the delta or epsilon. It is important that you ONLY highlight the number before you begin typing.