NAME
DATE
1-2
PERIOD
Study Guide and Intervention
Linear Measure
Measure Line Segments A part of a line between two endpoints is called a line
segment. The lengths of 𝑀𝑁 and 𝑅𝑆 are written as MN and RS. All measurements are
approximations dependent upon the smallest unit of measure available on the measuring
instrument.
Find the length of 𝑴𝑵.
Example 1
M
N
cm
1
2
3
Find the length of 𝑹𝑺.
Example 2
R
4
S
in.
1
2
The long marks are inches and the short
marks are quarter inches. Points S is closer
3
to the 1 inch mark. The length of 𝑅𝑆
The long marks are centimeters, and the
shorter marks are millimeters. There are
10 millimeters for each centimeter. The
length of 𝑀𝑁 is about 34 millimeters.
4
3
is about 1 inches.
4
Exercises
Find the length of each line segment or object.
B
1. A
cm
1
2
T
2. S
3
in.
3.
1
4.
in.
1
2
cm
5.
1
2
3
6.
cm
Chapter 1
1
2
3
4
5
in.
6
12
1
2
Glencoe Geometry
NAME
DATE
1-2
PERIOD
Study Guide and Intervention
(continued)
Linear Measure
Calculate Measures On ⃡𝑃𝑄, to say that point M is
between points P and Q means P, Q, and M are collinear
and PM + MQ = PQ.
M
Q
P
⃡ , AB = BC = 3 cm. We can say that the segments are
On 𝐴𝐶
B
A
C
congruent segments, or 𝐴𝐵 ≅ 𝐵𝐶. Slashes on the figure indicate
which segments are congruent.
1.2 cm
E
Example 2
Find EF.
2x + 5
1.9 cm
D
Find x and AC.
x
A
F
2x
B
C
B is between A and C.
AB + BC = AC
Betweenness of points
x + 2x = 2x + 5
Substitution
3x = 2x + 5
Add x + 2x.
x=5
Simplify.
AC = 2x + 5 = 2(5) + 5 = 15
Point D is between E and F. Calculate EF
by adding ED and DF.
ED + DF = EF
Betweenness of points
1.2 + 1.9 = EF
Substitution
Simplify.
3.1 = EF
Therefore, EF is 3.1 centimeters long.
Exercises
Find the measurement of each segment. Assume that each figure is not drawn to scale.
2.0 cm
1. RT
R
2.5 cm
2. BC
S
3. XZ
T
1
3
2
4
3 in.
X
Y
in.
6 in.
A
3
2 in. B
6 cm
4. WX
W
Z
C
4
X
Y
ALGEBRA Find the value of x and RS if S is between R and T.
5. RS = 5x, ST = 3x, and RT = 48
6. RS = 2x, ST = 5x + 4, and RT = 32
7. RS = 6x, ST =12, and RT = 72
8. RS = 4x, ST = 4x, and RT = 24
Determine whether each pair of segments is congruent.
10. 𝑋𝑌, 𝑌𝑍
9. 𝐴𝐵, 𝐶𝐷
A
11 cm
X
D
5 cm
5 cm
B
11 cm
5x – 1
3x + 5
C
Y
Z
9x
2
Chapter 1
13
Glencoe Geometry
Lesson 1-2
Example 1