# Thread: TI-89 Titanium, FINDING AN INTERSECTION

1. ## TI-89 Titanium, FINDING AN INTERSECTION

Could you tell me how to find an intersection?

I get to the step where you need to do things with lower and higher bounds and then after that it supposed to show the intersection point of the graph however it just says this: intersection(and no point)

2. Originally Posted by tupac
Could you tell me how to find an intersection?

I get to the step where you need to do things with lower and higher bounds and then after that it supposed to show the intersection point of the graph however it just says this: intersection(and no point)
Are you trying to find the intersection point of two graphs that are both displayed?

After you've entered the upper bound of the intersection point of interest you should get the coordinates after a few moments. Are you sure you've got more than one graph displayed and that your bounds are OK?

I can't think of any mode settings that would cause the coordinates not to be given if you've followed the process correctly.

3. For example i have these functions: y=2x and y=-2x, after i do the bound things it points where the intersection is but does not give me the numbers. This is as descriptive as it gets.

4. Originally Posted by tupac
For example i have these functions: y=2x and y=-2x, after i do the bound things it points where the intersection is but does not give me the numbers. This is as descriptive as it gets.
State all the keystrokes/commands you are using.

5. I discovered how to get the points.

ok, first i went to the screen where my graphs are then i pressed f1 and then pressed FORMAT. After that a window opens and where it says COORDINATES for my calculator it said OFF, i changed it to RECT. and then i graphed the functions again and i was able to find the point(s) of intersection

6. Originally Posted by tupac
I discovered how to get the points.

ok, first i went to the screen where my graphs are then i pressed f1 and then pressed FORMAT. After that a window opens and where it says COORDINATES for my calculator it said OFF, i changed it to RECT. and then i graphed the functions again and i was able to find the point(s) of intersection

7. Can a Ti89Ti find the equation of the line of intersection of two planes?

8. Originally Posted by shailen.sobhee
Can a Ti89Ti find the equation of the line of intersection of two planes?
Yes.

Treat the equations of the two planes as two equations to be solved simultaneously. The parametric solution gives the parametric equations of the line of intersection (when a solution exists, of course).