Texas Instruments TI-89 User Manual page 34

Constructing Perpendicular and Parallel Lines
Constructing a
Parallel Line
Note: The order of steps 3
and 4 can be reversed.
Note: You can move the
parallel line by dragging the
point through which the line
passes or by changing the
orientation of the object to
which it is parallel.
TI-89 / TI-92 Plus / Voyage™ 200 PLT Cabri Geometry App
The tool creates a line that passes through a point and is
Parallel Line
parallel to a selected linear object (line, segment, ray, vector, side of
a polygon, or axis).
1. Create any object having linear
properties such as the triangle shown
in this example.
2. Press † and select
2:Parallel Line
3. Move the pointer to the line,
segment, ray, vector, or side of a
polygon that will be parallel to the
constructed line and press ¸.
4. Move the pointer to a point through
which the parallel line will pass and
press ¸.
5. Drag one of the vertices of the
triangle to change its orientation.
(continued)
.
Select a linear object.
Select a point.
A dependent parallel line is
drawn.
Change the orientation.
30