Shape 

Copyright David & Cynthia Thomas, 2009

Chapter One: Concept Cards

Mathematical understanding encompasses more than facts and rules.  It recognizes and exploits relationships.  The concept card seen in Figure 1.25 does more than summarize geometric ideas relative to a given topic.  It shows how those ideas are related to one another. 

EXERCISE FORMAT: Construct and/or duplicate a given triangle using the strategy Angle-Side-Angle.

CONCEPT MODEL:

STEPS:

Step 1	A random point A’ is plotted on a working line.
Step 2	Using A’ as the center and segment AB in as the radius, a circle is drawn.  An intersection of this circle and the working line is labeled point B’.  Consequently, segment A’B’ is congruent to segment AB.
Step 3	Using the angle copying strategy demonstrated in Table 1.5, a ray is constructed with endpoint A’.
Step 4	Using the angle copying strategy demonstrated in Table 1.5, a ray is constructed with endpoint B’.
Step 5	The intersection of these two rays is labeled point C’, creating .

CONSTRUCTION:

Figure 1.25: Concept Model for Angle-Side-Angle