Texas Instruments TI-83 - Example 9 Solving an Inequality Involving Absolute Value

SOLUTION
Graph Y
1
= -5, Y
2
= 3x - 2, and Y
3
= 1 using the viewing window Xmin = -8, Xmax = 8,
Xscl = 1, Ymin = -8, Ymax = 4, Yscl = 1. We wish to find the point of intersection
between Y
1
and Y
2
and the point of intersection between Y
2
and Y
3
. We will first find
the point of intersection between Y
1
and Y
2
. After graphing all three equations, bring up
the CALC menu and select 5:
INTERSECT. When First Curve?
appears, the cursor should be on Y
1
.
Move the cursor near the point of
intersection and press ENTER.
After pressing ENTER, the cursor automatically jumps to Y
2
. Again, move the cursor
near the point of intersection.
Press ENTER a third time and you obtain the point of intersection as (-1, -5).
We now wish to find the point of intersection between Y
2
and Y
3
. Bring up the CALC
menu and select 5: INTERSECT. The first curve is on Y
1
, but we want it on Y
2
. This is
accomplished by pressing the down arrow. Move the cursor near the point of intersection
and press ENTER. The cursor jumps to Y
3
. Again, move the cursor near the point of
intersection and press ENTER. Press ENTER a third time to obtain your solution, (1, 1).
We know we are TRACEing
on Y
1
because of this!!