1. Geom41.notebook November 01, 2011
BELL WORK:
State ALWAYS, SOMETIMES, or NEVER:
1. A median is an altitude.
2. A right triangle is congruent to an equilateral triangle.
Agenda for the day:
• 4.1
• exit slip
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2. Geom41.notebook November 01, 2011
4.1 Midpoints and Detours
After this lesson, you should be able to:
1. Calculate the location of a midpoint using the midpoint formula.
2. Use detours in proofs.
On the number line to the right, A M B
determine the coordinate for M 2 14
if M is the midpoint of AB:
The Midpoint Formula:
Sometimes it is necessary to prove more than
one pair of triangles congruent in order to
reach a conclusion.
We call such proofs detour proofs.
Let's look at the example on p.169.
Extra examples: see the sample problems on pp.171 and 172
The procedure for detour proofs is on p.170
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3. Geom41.notebook November 01, 2011
Detour proof: p.173 #2
M
Q
P N
Given:
S
Prove:
Exit Slip: p.172 #1
You don't have to write the entire proof, just
number 37 and fill in the blanks.
Homework: 4.1 Practice Worksheet
due Thursday
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