Transcript 1.3 Segments and Measure

1.3 Segments and
Measure
The segment postulate
Distance Formula
Postulate (or Axioms) accepted
facts
What goes up, must come down.
You can not be in two places at the same
time.
Can you think of others?
The Ruler Postulate

Points on a line can be matched with
numbers. These points are called
Coordinates
This would gives us a number line
Definition of distance


Distance is the space between two Coordinate
points
To find Distance we use the Absolute Value of
the difference of the two points
2
24
| 2 – 24| = | 22| so 22
Remember the distance between me and you is the
same no matter who hold the end of the tape
measure.
Segment Addition
If B is between A and C, then AB + BC = AC
Or
If AB + BC = AC, then B is between A and C
A
B
C
Segment with number
When we use AB we mean a number and
AB is a shape
Lets say AB = 8 and BC = 4, then AC = 12
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A
B
C
The definition of Congruent
For two shapes to be congruent, they have
the same shape and size.
We denote congruent with 
AB = AD
Numbers
AB  AD
Shapes
The Distance Formula

If A (x1, y1) and B (x2, y2) are points in a
coordinate plane, then
AB  ( x 2  x1 ) 2  ( y 2  y1 ) 2

A:(1,3); B:(5,6)
AB 
5  1
2
 6  3  16  9  25  5
2
Homework
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Page 21- 24 # 20, 22, 23-30, 31- 41 odd,
45, 46, 53, 54, 58