Turned in tessellation work and took first triangle congruence assessment.
Homework
#1-3 on this handout
Resources
great video on how to write paragraph proofs: link
another good paragraph proof example: link
paragraph proof on complicated AAS overlapping case: link
Passed back assessments and learned how to write two-column proofs, which are basically just outline versions of the paragraphs we've been writing. Looked at new pieces of evidence embedded in the given or the figures, which include deductions based on definitions of words used (often "midpoint" or "bisect" or "perpendicular"). Then did proofs in groups around the room on whiteboards and did a gallery walk of problems other groups completed.
Notes from board
handout from class, done in class
Homework
p. 159 #8-12
note that none of these will use cpctc
Resources
proof using midpoint : LINK
proof using parallel lines : LINK
proof using an angle bisector: LINK
several proof examples: LINK
mixed examples of proofs: LINK
Warm up was an angle chase that utilized a theorem we proved last class without realizing it: the fact that if a triangle is isosceles, then its base angles are congruent. Went over homework and reviewed triangle types, classified both by side lengths and angle sizes. Then did a more challenging, complex angle chase. Finally did more whiteboard work in groups on proofs dealing with overlapping triangles and multiple congruences.
Notes from board
Homework
p. 177-8: #4,7,8,10 [write 2 as 2-column proofs, and 2 as paragraphs]
assessment on proof next class
Resources
See Tues/Weds. above