Materials: TI-80 graphing calculator, graph paper
Before you start, clear the calculator’s memory. Press
MEM and select the Reset settings until the
display indicates that the memory is cleared.
1. a. Write three ordered pairs that are solutions to the
equation y = 3x + 1.
b. Write three ordered pairs that are solutions to the
inequality y > 3x + 1.
c. Write three ordered pairs that are solutions to the
inequality y < 3x + 1.
d. On the calculator, press DRAW (2nd and
PRGM) and select Shade_Y>. Type in
3x + 1 and press ENTER. Sketch the display on the calculator onto graph
paper.
[Note: On higher- numbered models , press Y= and enter y = 3x + 1. Press
DRAW ,
then select Shade and input the entry Shade (Y1, 10). To display Y1, press
VARS;
select Y-VARS, then select Function followed by Y1.]
e. Describe where the points for the ordered pairs in 1.a.
are on the display: on the line y = 3x
+ 1, on the shaded side of the line , or on the unshaded side of the line.
f. Describe where the points for the ordered pairs in 1.b.
are on the display.
g. Describe where the points for the ordered pairs in 1.c.
are on the display.
1. h. How do you think the graphs of y > 3x + 1 and y ≥ 3x
+ 1 compare ?
2. a. Write three ordered pairs that are solutions to the
inequality y < 2x – 3.
b. On the calculator, press DRAW (2nd and
PRGM) and select Shade_Y<. Type in
2x – 3 and press ENTER. Sketch the display on the calculator onto graph
paper.
[Note: On higher numbered models , press Y= and enter y = 2x – 3. Press
DRAW then
select Shade and input the entry Shade (–10, Y1). To display Y1, press VARS;
select
Y-VARS, then select Function followed by Y1.]
c. Describe where the points for the ordered pairs in 2.a.
are on the display.
5. How is graphing an inequality like or unlike graphing
an equation? Use examples to support
your answer.
