# Parallel And Perpendicular Lines Worksheet Page 35

A Preview of Lesson 3-6
Points of Intersection
You can use a TI-83 Plus graphing calculator to determine the points of intersection
of a transversal and two parallel lines.
Example
m
t
m
t
Parallel lines
and
are cut by a transversal
. The equations of ,
, and
1
1
are y
x
4, y
x
6, and y
2x
1, respectively. Use a graphing
2
2
t
m
calculator to determine the points of intersection of
with
and
.
Enter the equations in the Y = list and graph in the standard viewing window.
:
1
2
X,T, , n
4
1
2
X,T, , n
ENTER
KEYSTROKES
( )
X,T, , n
6
ENTER
2
1
ZOOM
6
Use the CALC menu to find the points of intersection.
t
t
m and
Find the intersection of
and
.
Find the intersection of
.
:
[CALC]
5
ENTER
2nd
KEYSTROKES
:
[CALC]
5
ENTER
2nd
KEYSTROKES
ENTER
ENTER
ENTER
ENTER
[ 10, 10 ] scl: 1 by [ 10, 10 ] scl: 1
[ 10, 10 ] scl: 1 by [ 10, 10 ] scl: 1
t
Lines
and
intersect at (2,
3).
t
m and
Lines
intersect at ( 2, 5).
Exercises
a
b
t
Parallel lines
and
are cut by a transversal
. Use a graphing calculator
a
b
to determine the points of intersection of t with
and
. Round to the
nearest tenth.
a
a
a
: y
2x
10
: y
x
3
: y
6
1.
2.
3.
b
b
b
: y
2x
2
: y
x
5
: y
0
1
t
t
t
: y
x
4
: y
x
6
: x
2
2
4
1
2
a
a
a
: y
3x
1
: y
x
2
: y
x
4.
5.
6.
5
6
3
4
1
5
b
b
b
: y
3x
3
: y
x
7
: y
x
5
6
1
2
1
5
t
t
t
: y
x
8
: y
x
: y
6x
2
3
4
158 Investigating Slope-Intercept Form
158 Chapter 3 Parallel and Perpendicular Lines