Transcript What you really need to know!

Lesson 10-1 Pages 492-497
Line and Angle
Relationships
Lesson Check Ch-9
What you will learn!
1. How to identify the relationships
of angles formed by two parallel
lines and a transversal.
2. How to identify the relationships
of vertical, adjacent,
complementary, and
supplementary angles.
Parallel lines
Corresponding angles
Transversal
Vertical angles
Interior angles
Adjacent angles
Exterior angles
Complementary angles
Alternate interior angles
Supplementary angles
Alternate exterior angles Perpendicular lines
What you really need to know!
When two parallel lines are intersected
by a third line called a transversal, eight
angles are formed!
What you really need to know!
Interior angles lie inside the
parallel lines!
3, 4,
5, 6
What you really need to know!
Exterior angles lie outside
the parallel lines!
1, 2,
7, 8
What you really need to know!
Alternate interior angles are on opposite
sides of the transversal and inside the
parallel lines!
3 and 5,
4 and 6
What you really need to know!
Alternate exterior angles are on opposite
sides of the transversal and outside the
parallel lines!
1 and 7,
2 and 8
What you really need to know!
Corresponding angles are in the same
positions on the parallel lines in relation to
the transversal!
1 and 5,
4 and 8,
2 and 6,
3 and 7
What you really need to know!
Example 1:
In the drawing,
m ║ n and t is
a transversal.
If m 7 = 123°,
find m 2 and
m 8.
Example 1:
m 2 = 57°
and
m 8 = 57°
Example 2:
If m D = 53° and  D and
 E are complementary,
what is m E?
A
B
C
D
53° 37° 127° 7°
Example 3:
Angles PQR and STU
are supplementary. If
m PQR = x – 15 and
m STU = x – 65, find
the measure of each
angle.
(x – 15) + (x – 65) = 180
2x – 80 = 180
2x = 260
x = 130
m PQR = 130 – 15 = 115°
m STU = 130 – 65 = 65°
Example 4:
A road crosses railroad tracks at
an angle as shown. If m1 =
131°, find the m6, and m5.
m6 = 49°
and
m5 = 131°
Page 495
Guided Practice
#’s 3-9
Read:
Pages 492-495 with
someone at home and
study examples!
Homework: Pages 496-497
#’s 10-31 all
#’s 35-36, 43-45
Lesson Check 10-1
Page
747
Lesson 10-1
Lesson Check 10-1