April 10 was a short day for 1st and 2nd due to testing.
Our goal today was to dig into the circle unit, constructing vocabulary terms for chord, secant, diameter, and tangent, as well as discovering/proving our first two circle properties, which are:
C-74 on p 353: A line tangent to a circle is perpendicular to a radius of the circle at the point of tangency.
C-75 on p 354: Two lines tangent to the same circle intersect to form congruent tangent segments (see sketch on p 353).
The attachment below includes HW as well as the new content to add to Geometric Truth (vocabulary and C-74-5). Follow instructions precisely. The problems for HW #6 are listed and needs explained on the same attachment.
We discovered C-74 by modeling a discus throw; we argued deductively for C-75 to be true because of congruent right triangles.
A couple problems that create difficulty with "seeing" were demonstrated, particularly using C-75 to find the perimeter of a circumscribed quadrilateral.
In some classes, we previewed the conjectures from section 9.2 about chords in circles (76-80).
Quizzes were viewed in all classes. Make-ups need to be done yesterday!!! You are always welcome to come by during advisory and go over your quiz with me to see what went wrong if it did not go well.
Our goal today was to dig into the circle unit, constructing vocabulary terms for chord, secant, diameter, and tangent, as well as discovering/proving our first two circle properties, which are:
C-74 on p 353: A line tangent to a circle is perpendicular to a radius of the circle at the point of tangency.
C-75 on p 354: Two lines tangent to the same circle intersect to form congruent tangent segments (see sketch on p 353).
The attachment below includes HW as well as the new content to add to Geometric Truth (vocabulary and C-74-5). Follow instructions precisely. The problems for HW #6 are listed and needs explained on the same attachment.
We discovered C-74 by modeling a discus throw; we argued deductively for C-75 to be true because of congruent right triangles.
A couple problems that create difficulty with "seeing" were demonstrated, particularly using C-75 to find the perimeter of a circumscribed quadrilateral.
In some classes, we previewed the conjectures from section 9.2 about chords in circles (76-80).
Quizzes were viewed in all classes. Make-ups need to be done yesterday!!! You are always welcome to come by during advisory and go over your quiz with me to see what went wrong if it did not go well.
hw_6_-_geometric_truth_entries_and_tangent_conjectures.docx |