1-2 LINEAR MEASURE

MEASURE LINE SEGMENTS

A line cannot be measured because its endpoints go on forever

A line segment can be measured because it has endpoints

A B

A B

FIND LENGTH IN METRIC UNITSExample 1

Find the length of using each ruler.

a)

b)

is about 42 mm.

is about 4.5 cm.

Find Length in Standard UnitsExample 2

116

216

316

416

516

616

716

816

916

1016

1116

1216

1316

1416

1516

1616

016

BETWEENESS OF POINTS

Point M is between points P and Q if and only if P, Q, and M are collinear and PM + MQ = PQ.

P QM

PM MQ

PQ

FIND MEASUREMENTS BY ADDING

Example 3

a) Find XZ, (assume that the figure is not drawn to scale.)

XZ = XY + YZ

= 5.3 + 2.6

= 7.9

XZ = 7.9 cm

X ZY5.3 cm

2.6 cm

Find Measurements by Subtracting

Example 4Find AB.

AC = AB + BC25.6 = AB + 11.1- 11.1 - 11.114.5 = ABAB = 14.5 m

A CB

25.6 m

11.1 m

Write and Solve Equations to Find MeasurementsExample 5a) Find the value of a and XY if Y is between X and Z.XZ = XY + YZ

X ZY

5a - 4

14

3a

❑2

❑2

𝑎=9

Write and Solve Equations to Find MeasurementsTWAP (Try with a Partner)Find the value of x and FG if F is between E and G.EG = EF + FG

E GF

45

7x5x - 3

❑12

❑12

F

VOCAB:

Congruent Segments: Segments that have the same measure. Use the symbol Example: Can lines be congruent??? Find some cong. Segments in the room.

≅𝐴𝐵≅𝐶𝐷

𝑁𝑂 ! ! ! !

Watch out!!!!Equal vs. congruentSEGMETNS are congruent but LENGTHS are =5≅ 5𝑋𝑌=𝐶𝐷NO!!!

!!

HW 1-2PAGE 18 (9-19 ODD, 20,

21-31 ODD, 37, 40)