NotesStep & Key Operation
*Use either pen touch or cursor to operate.
Display
EL-9650/9600c Graphing Calculator
2-1
Enter y = 3(4 - 2x) for Y1 and
y = 5 - x for Y2.
*
(7 times) (4 times)
*
2-2
View the graph.
2-3
Access the Set Shade screen.
*
*
2-4
Set up the shading.
Since the inequality being
solved is Y1
≥
Y2, the solu-
tion is where the graph of Y1
is “on the top” and Y2 is “on
the bottom.”
*
*
*
2-5
View the shaded region.
2-6
Find where the graphs intersect and
solve the inequality.
The point of intersection is
(1.4, 3.6). Since the shaded
region is to the left of x = 1.4,
the solution to the inequality
3(4 - 2x)
≥
5 - x is all values
of x such that x
≤
1.4.
*
Graphical solution methods not only offer instructive visualization of the solution
process, but they can be applied to inequalities that are often difficult to solve
algebraically. The EL-9650/9600c allows the solution region to be indicated visually
using the Shade feature. Also, the points of intersection can be obtained easily.
7-1
GRAPH
Y=
DEL
—
—
——
2
G
1
5
ENTER
2nd F CALC
2nd F
DRAW
GRAPH
X/
/T/n