Parallel And Perpendicular Lines - Sharp EL-9900 Handbook Vol. 1 Operation Manual

Parallel and Perpendicular Lines

Parallel and perpendicular lines can be drawn by changing the slope of the linear equation
and the y intercept. A linear equation of y in terms of x can be expressed by the slope-
intercept form y = mx + b, where m is the slope and b is the y-intercept.
Parallel lines have an equal slope with different y-intercepts. Perpendicular lines have
slopes that are negative reciprocals of each other (m = -
verified by graphing these lines.
Example
Graph parallel lines and perpendicular lines.
1.
Graph the equations y = 3x + 1 and y = 3x + 2.
2.
Graph the equations y = 3x - 1 and y = -
Before There may be differences in the results of calculations and graph plotting depending on the setting.
Starting
Return all settings to the default value and delete all data.
Set the zoom to the decimal window:
Step & Key Operation
1
1
Enter the equations y = 3x + 1 for
-
Y1 and y = 3x + 2 for Y2.
n
Y= 3 X/ /T/
+
n
3 2
X/ /T/
1
2
View the graphs.
-
GRAPH
2
1
-
Enter the equations y = 3x - 1 for
1
Y1 and y = - x + 1 for Y2.
3
Y=
CL 3
X/ /T/
-
( ) a /b
CL 1
+
1
ZOOM
+
1
ENTER
n
—
1 ENTER
n
3
X/ /T/
EL-9900 Graphing Calculator
1
). These characteristics can be
m
1
x + 1.
3
( )
C 7
ENTER ALPHA
Display
These lines have an equal
slope but different y-intercepts.
They are called parallel, and
will not intersect.
Notes
3-2