1. Geom4­4.notebook November 09, 2011
BELL WORK:
If CD is the hypotenuse of a right
triangle CAD, find all possible values
for the coordinates of A. (p.183 #8)
y
5
4
3
D
2
1
x
C
­5 ­4 ­3 ­2 ­1 0 1 2 3 4 5
­1
­2
­3
­4
­5
Agenda for the day:
• questions on p.182 #2­7
• 4.4 ­ The equidistance theorems
• exit slip
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2. Geom4­4.notebook November 09, 2011
Questions??
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3. Geom4­4.notebook November 09, 2011
`
4.4 ­ The Equidistance Theorems
Before we begin, use pp.184 and 185 to write a definition for
each of the following words:
distance ­
equidistant ­
perpendicular bisector ­
Postulate: A line segment is the shortest path between two points.
Theorem: If two points are each equidistant from the endpoints of a
segment, then the two points determine the perpendicular bisector of
that segment.
P
A B
Q
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4. Geom4­4.notebook November 09, 2011
Theorem: If a point is on the perpendicular bisector of a segment,
then it is equidistant from the endpoints of that segment.
PQ is the perpendicular bisector of AB. P
A Q B
Given: 1 = 2 A
3 = 4
Prove: AE bis. BD
1 E 2
B D
3 4
C
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5. Geom4­4.notebook November 09, 2011
Given: AB = AD ; BC = CD A
Prove: BE = ED
C
B D
E
EXIT SLIP: p.187 #1
You will need two points that are equidistant from A
and B. One is in your given. The other can be stated
after you draw auxiliary lines.
Homework: p.187 #2­6
due Thursday
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