Paper plate explorations: created and measured inscribed angles and noted their relationships to central angles so long as they intersect ("subtend") the same arc. If you were confused today, here are some applets to play with:
Major and minor arcs: link
What is a central angle: link
What is an inscribed angle: link
Central Angle and Inscribed Angle relationship: link
We also drew chords on the reverse of the paper plate, measured them, and noticed the following:
Chord-Chord theorem: link
Notes from board
Homework:
Worksheet #1-8, 13, 15 [CO-A1d] (copy of worksheet here)
Resources
amazing video which helps with problems like #1-8 (link)
lost on 13 and 15? Try them out...we'll go over them in class.
Warm up dealing with radius and chords and their relationship (see here for a similar task--I did not provide the dotted line) and then went over the homework. Then worked through several examples on inscribed angles, central angles, and arcs. See below for resources for homework help. Also practiced with more chord examples dealing with the radius. [see example here: link 1 link 2]
Then reviewed triangle congruence proofs to show that tangents to a circle from a common point are congruent (here is the proof another proof). Then applied these concepts in a problem dealing with an inscribed circle within a triangle and using the idea of congruent tangents to make the problem very easy.
Notes from board
Homework
p. 348 #10, 12
p. 369: #1,3
[C-A2a]
Assessment on Thurs/Fri!!
Resources
Finding arc and inscribed angle measures example: link
Thursday/Friday
Opened class with an estimation warm up. Then went over homework on arc measure and radius-chord relationships. Took assessment on circles. Then did tasks regarding arc length, leading to the arc length formula as an application of proportions.
Homework:
Watch and take notes on this video (GPE-A1a)