1. CALC Menu - intersect CALC|intersect is used to find the intersection point of two curves. Example Find all points of intersection for the functions given by Enter function f into Y1 and function g into Y2. Use a ZOOM|ZStandard window.

2. Slide 2 CALC Menu - intersect Example Go to CALC|intersect. The following calculator screen appears. Note that: (1) Function f, or Y1, is shown at the top left of the screen. (2) The trace cursor is located at the point (0,-4) on the graph of function f.

3. Slide 3 CALC Menu - intersect Example The calculator is asking for the “First curve?” to be identified. Press ENTER to select function f, or Y1. (3) There are three points of intersection on the two curves. It is necessary to specify which point is to be found. This is done in the last step.

4. Slide 4 CALC Menu - intersect Example Note that function g, or Y2, is now shown at the top left corner of the screen. Also, the trace cursor is located at the point (0,1) on the graph of function g. The calculator is asking for the “Second curve?” to be identified. Press ENTER to select function g, or Y2.

5. Slide 5 CALC Menu - intersect Example The calculator is asking for a “Guess?”. This is necessary to identify which of the three points is to be found. There are two different ways to accomplish this. Use only one of the two methods on the next slide.

6. Slide 6 CALC Menu - intersect Example (1) Use the right arrow key to move the trace cursor to the far right intersection point and press ENTER. (2) A second method is to type in an x-value that is close to the intersection point, say x = 2. Enter a 2 and then press ENTER. This is usually much faster.

7. Slide 7 CALC Menu - intersect Example The point of intersection is approximately at (1.45,2.45). The process can now be repeated to find the other two points of intersection. Start with the point on the far left.

8. Slide 8 CALC Menu - intersect Example Go to CALC|intersect. Note that the trace cursor is still at the right intersection point. Press ENTER twice to accept Y1 as the first curve and Y2 as the second curve. For a guess, enter -3. The answer is approximately (-3.45, -2.45)

9. Slide 9 CALC Menu - intersect Example Find the third point of intersection. Answer: (-1,0)

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