Go Graphic

# Online Tutorial -CG50: How to Use Modify

## Video Transcript

In this tutorial, we'll be looking at modify in the graph menu. This enables us to explore equations which contain unknown coefficients, whose values can be modified. In modify the ordinary graph drawing tools may not be active, so we'll also look at how to return to the draw menu to use zoom or G-Solve and so on. To work along with this tutorial, you may find it easiest to reset the calculator before starting so that your screen much is the one in the video.

Choose graph mode and use the Alpha key and the X Theta T key to type in the equation with the constants. And then press execute to enter and then press modify instead of draw. The calculator uses the previous values for A and B. In my case, it has drawn Y equals zero X plus zero. Notice that the values of A and B are shown on the left of the display and the A is currently highlighted.

Scroll to the right, to increase the value of A and it increases by one each time. Scroll down to select B, and then you can scroll to the left to decrease the value of B. Notice the yellow line shows where the graph had previously been. If you scroll down to step, you can change the step size and you can simply type the value you want - as indeed you can for A and B as well. And now when B is modified, it changes by 0.5 each time.

Press exit to return to graph mode and now you can use the other tools like zoom and G-Solve and view window should you wish to. If you exit and go back to the list of functions, you can delete the equation that's already there and then use the tools menu in built in and scroll down to the completed square form of a quadratic and select. Go to modify and explore the effect of changing the values of A and B and C.

Here's a challenge for you. Can you find the values of A, B and C, which give you this graph? In graph mode, you can draw a family plot with several values for the constant shown together.