Find Points of Intersection on the TI-83 Plus
You can use the TI-83 Plus graphing calculator to locate the point of intersection of two graphs. Doing so with the arrow keys gives you an approximation of that point, but this method rarely gives you the actual point of intersection. To accurately find the coordinates of the point where two functions intersect, perform the following steps:
Graph the functions in a viewing window that contains the point of intersection of the functions.
Set the Format menu to ExprOn and CoordOn.
Press [2nd][TRACE] to access the Calculate menu.
Press  to select the intersect option.
Select the first function.
If the name of one of the intersecting functions does not appear at the top of the screen, repeatedly press
until it does. When the cursor is on one of the intersecting functions, press [ENTER] to select it.
Select the second function.
If the calculator does not automatically display the name of the second intersecting function at the top of the screen, repeatedly press
until it does. When the cursor is on the second intersecting function, press [ENTER] to select it.
to move the cursor as close to the point of intersection as possible.
Press [ENTER] to display the coordinates of the point of intersection.