On B Day, we began with a practice quiz that covered the similarity and dilation content before the holiday break. A day will do that practice quiz on Thursday.
Every class but 2nd and 3rd got to practice at least one dilation problem.
Goals for the day: remember what you learned before the break, learn how to find missing information when an altitude is dropped from the right angle in a right triangle (3 similar triangles), discover and apply C-42 and 43 on pp 273-4 about midsegments in triangles, and realize that altitudes, medians, and angle bisectors have the same ratio as sides in similar figures.
The best practice problem for the right triangle issue is p 575:8. There are two of these problems on the homework, one of which is a mini-investigation to make a generalization.
On A day, we also discovered and learned how to apply C-100 on pp 604-5: when a parallel line crosses two sides of a triangle, it creates proportional segments. The converse is true also. This also works when there are more than one parallel line. We also looked at when it does not work: it does not help you solve for the third side that is not connected by the parallel lines (see problems on p 607).
C-42 (p 273) - "four congruent triangles", C-43 (p 274) "parallel" and "half the length of the third side".
On A-day, we practiced indirect measurement from p 582-3:1-2,5.
HW #10: p 575:13-15, p 582-4:3-4,6-7,11,13; p 588-90:1-3,14,19, p 275-6: 4-5.
Attached below: practice quiz for B day.