Monday, April 13th, 2009

1. Welcome back from Spring Break!

2. Please read 306 in the textbook to warm-up. Can you answer the questions? #1 is f.

3. Lots of investigations to do today. Work with a partner. Talk about geometry. Use geogebra to explore the concepts. We will share out as class progresses. It is very important to stay focused and work hard.

4. Investigation results:

Investigation 1 on page 307:
Define a central angle: A central angle has its vertex at the ____________________.
Define an inscribed angle: An inscribed angle has its vertex on the ___________________
and its sides are _____________.

Investigation 2 on page 307. Use geogebra. Carefully follow all the steps. Fill in the blank:
Chord central angles conjecture: If two chords in a circle are congruent, then they determine two central angles that are _____________.
Chord arcs conjecture: If two chords in a circle are congruent, then their _________________ are congruent.


Investigation 3 on page 309. Use geogebra. Fill in the blank:
Perpendicular to a chord conjecture: The perpendicular from the center of a circle to a chord is the ______________ of the chord.
Chord distance to center conjecture: Two congruent chords in a circle are ________________ from the center of the circle.

Investigation 4 on page 309. Use geogebra. Fill in the blank:
Perpendicular bisectors of a chord conjecture: The perpendicular bisector of a chord ___________________________________________.

5. Do question 1 through 9 on page 310 for homework.