"Where do the equations y=x and y=-2x+3 intersect?"One way to find the solution is to solve the two equations algebraically using simultaneous equations.
First open and clear the main work pane.
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Press the blue Keyboard button and bring up the soft keyboard. Select the 2D tab.
You should be able to see a button with a bracket and two small boxes (circled below in red). Press it.
You should see the simultaneous equation template in the main pane.
(Update 1/6/2010: Press it twice to add a third equation line!)
Click on the box below it and type y=-2x+3
In the third box to the right of the vertical line type x,y (the variables we wish to solve).
Hit the exe button.
The answer (x=1, y=1) should appear.
Here is a link to other CAS calculator posts.