Chương I. §10. Trung điểm của đoạn thẳng

On the ray Ox, draw two line segments OM and ON so that OM=3cm, ON=6cm.. The point M of line segment AB is the point which is located between A, B and has the equal distancefrom A, B.. A

Unit 10 MIDPOINT

On the ray Ox, draw two line segments OM and

ON so that OM=3cm, ON=6cm compute the length of MN? Compare OM and MN

REVIEW

2

QUESTION

⇔OM = MN

Point M divides line segment ON into 2 congruent parts

On the ray Ox, draw two

line segments OM and ON

so that OM=3cm, ON=6cm

Calculate the length of

The point M of line segment AB is the point which is located between A, B and has the equal distance

from A, B

A midpoint divides a line segment into two congruent segments

Note: The midpoint of line segment AB is also known as the central point of line segment AB

UNIT 10 MIDPOINT OF A LINE SEGMENT

1 DEFINITION

Point M is midpoint of line

segment AB

APPLY: In each case, is m midpoint of line segment Ab or not, and why?

M is midpoint of line segment AB

2 How to draw the midpoint of a line

2 How to draw the midpoint of a line

segment?

ii) Folding paper: Make a midpoint on paper sheet, fold it so that

2 sides overlap to define a midpoint

8

B

B

B

A B

B

B

B

A B

A B

A B

B

B

B

A B

B

B

B

A M B

5,

2 2

Midpoint geometry in real life

2

practical exercise

Determine the midpoint of your pen or pencil by preparedrope You only have 30 seconds for this!!!

MN = 40 cm

Bonus : Let H is midpoint of line segment MN, and MH=20 cm

Calculate the length of line segment MN ?

20cm

?cm

H

Consolidating Lesson

Remind : when point M is called a midpoint

of line segment AB?

Thanks for your atention

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