Manual

148 Geometry
Symbolic view in detail
Every object—whether a
point, segment, line,
polygon, or curve—is given
a name, and its definition is
displayed in Symbolic view
(
Y). The name is the
name for it you see in Plot
view, but prefixed by “G”.
Thus a point labeled A in Plot view is given the name GA in
Symbolic view.
The G-prefixed name is a variable that can be read by the
computer algebra system (CAS). Thus in the CAS you can
include such variables in calculations. Note in the illustration
above that GC is the name of the variable that represents a
circle drawn in Plot view. If you are working in the CAS and
wanted to know what the area of that circle is, you could enter
area(GC) and press
E. (The CAS is explained in
chapter 3.)
g
Selects the intersection drawing tool. Fol-
low the instructions on the screen (or see
page 154).
j
Selects the line drawing tool. Follow the
instructions on the screen (or see page
156 ) .
B
Selects the point drawing tool. Follow the
instructions on the screen (or see page
153 ) .
r
Selects the segment drawing tool. Follow
the instructions on the screen (or see
page 156).
n
Selects the triangle drawing tool. Follow
the instructions on the screen (or see
page 157).
t
Undo.
Key
Result in Plot view (Continued)