Two polygons are congruent if their corresponding sides are congruent and their corresponding angle are congruent. (We learned this back in our vocab unit and it should be in your geometric truth.) But can triangles be shown to be congruent with LESS THAN these 6 pieces of congruent information? Two pieces is not enough... we would all have different triangles. p 169:1-2 show us that that everyone in the room constructed the same triangle given the three sides and no angles. And everyone one in the room constructed the same triangle given two sides and the angle between them. This leads us to Triangle Congruence Shortcuts. See p 219-221. SSS and SAS may be written up from pp 220-221 using sketches from p 219 (write in Geometric Truth).
HW #3 is p 222-3:1-6, 8-15. Write which triangles are congruent, name in the correct sequence of corresponding vertices, and state whether you know by the SSS shortcut or the SAS shortcut. There are four of these problems that are either named incorrectly or do not have enough information for SSS or SAS shortcut. SSA is not a legitimate shortcut (see problem 5 on p 170).
We went over HW #2, took a grade, did a practice worksheet to make sure we understood, then took a 22 pt quiz over 4.1-3. This may be made up at the beginning of the next block since it is so short and quick.
If you need more help with the shortcuts, choose Pre-AP Geometry, Look for Resources, Condensed Lessons for Triangle Unit, and read about section 4.4.
MAKE-UPS and retakes for the Construction Unit need to be done by Thursday, Nov 2. Come during A&E tomorrow to get more info. You can also come before school on Wednesday to get help. Send me a remind message for a hall pass.
The worksheet is attached to the previous blog post.