1B worked on the practice assessment. A-block classes reviewed triangle similarity criteria, then learned about proportionality within triangles and solved for missing lengths given parallels (or determining parallels by showing proportions). Passed out practice test
Notes from board
Homework
finish practice assessment [blank copy] [SOLUTIONS]
Resources
SRT-A2a: determining if similar; finding missing sides if simil: link1 (made by me!) link 2
SRT-A3: determining if two triangles are similar, criteria: link 1 (by me!) link2
SRT-B4a: finding missing side lengths with parallels: link link2
SRT-B4a: figuring out if a segment is parallel or not: link
SRT-A1a: performing a dilation on the coordinate plane: link
SRT-A1a: dilation's effect on area: link
SRT-A1b: finding center and scale factor of dilation: link1 link2
SRT-A1b: properties of dilations, esp. parallel lines: link
Warmup dealt with two problems involving the Pythagorean theorem. Gave out third quarter learning targets and passed back assessments. Defined the term altitude as it relates to triangles and used this idea to create an altitude out of a right triangle with construction paper. This led to 2 new triangles being formed, which we discovered were similar by Angle-Angle. Then we labeled the sides in a particular way and found a special pattern/formula that relates the height of a right triangle and the two parts of the hypotenuse it divides. This is called the geometric mean, and we used the formula and/or self-similar triangles to find missing lengths.
Notes from board
3rd Quarter Learning Targets
Homework
p. 280 #9 parts a thru f
next assessment: Jan 30 or 31st
Resources
basic premise of geometric mean: link
several geometric mean examples worked out: link1 link2
multiple part geometric mean: link