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4-3-1
Drawing a Conics Graph
4-3 Drawing a Conics Graph
This section provides examples that show how to draw various types of conics graphs.
Drawing a Parabola
A parabola can be drawn with either a horizontal or vertical orientation. The parabola type is
determined by the direction of its principal axis.
k
Drawing a Parabola that Opens Horizontally
A parabola with a horizontal axis is one whose principal axis is parallel to the
x
-axis. There
are two possible equations for a parabola with a horizontal axis:
x
= A(
y
– K)
2
+ H and
x
= A
y
2
+ B
y
+ C.
Example 1:
To draw the parabola
x
= 2(
y
– 1)
2
– 2
u
ClassPad Operation
(1) On the Conics Editor window, tap
q
, or tap [Form] and then [Insert Conics Form].
• This displays the Select Conics Form dialog box.
(2) Select “X = A(Y – K)
2
+ H” and then tap [OK].
• This closes the Select Conics Form dialog box, and displays the selected equation in
the Conics Editor window.
(3) Change the coefficients of the equation as follows: A = 2, K = 1, H = –2.
(4) Tap
^
to graph the equation.
