HolcombMath

Thursday, May 28, 2009

Geometry (Class 84)

Lesson Title
Circles (4): Intersecting Chords

Overview
The opener today provides time for students to continue working on problems involving central angles, inscribed angles, and tangents. The lesson focuses on the relationships resulting from chords which intersect.
Textbook Sections
§10.2 (Txt. p.606) Arcs and Chords

Vocabulary
circle
circumference
diameter
radius
chord
secant
tangent
central angle
arc
arc length
arc angle
inscribed angle
inscribed arc

Key Attitudes
Math is about building up understanding one idea at a time.

Key Ideas
If two chords intersect in the interior of a circle, then the product of the lengths of the segments of one chord is equal to the product of the lengths of the segments of the other chord.
In the same circle, or in congruent circles, tow minor arcs are congruent if an only if their corresponding chords are congruent.
If a diameter of a circle is perpendicular to a chord, then the diameter bisects the chord and its arc.
If one chord is a perpendicular bisector of another, then the first chord is a diameter.
In the same circle, or congruent circles, two chords are congruent if and only if they are equidistant from the center of the circle.
Key Skills
I can use properties of intersecting chords to solve problems.
Turn-In (#83)
Chapter 10- Lesson 1: Practice 2- ALL

Handouts
Chapter 10: Lesson 3- Intersecting Chords
Chapter 10- Lesson 3: Intersecting Chords Practice 1

Assignment
Work towards finishing the problems at the end of Lessons 1, 2, and 3 for Chapter 10
Disclaimer- The assignment as stated in class is the official assignment. Every effort is made to keep this posting accurate, but you should refer to what was stated in class as the final word.