Quote of the Day:
"The function of education is to teach one to think  
   intensively and to think critically. Intelligence plus 
   character - that is the goal of true education." 
    -- Martin Luther King, jr

Objective:
The student will review the definition of a parabola.

1. How do we define a parabola (the locus definition)?

   Definition: A parabola is the set of points equidistant 
               from a given point and a given line.
               The given point is called the focus and the 
               given line is called the directrix. 


2. Distribute a copy of the "parabola paper" to each 
   student.  Have each student trace out a parabola while I 
   do one at the overhead.  The purpose of this is to have
   students understand the definition of the parabola by 
   locating points which are the same distant to a point as 
   they are to a line.

        Parabola Paper

3. Develop the equation for a parabola which opens up and 
   has its vertex at the origin.
   
   Let p = distance from the vertex to the focus.
   Then the coordinates of the focus are (o, p).
   The vertex would be (0, 0).
   The equation of the directrix would be  y = -p.

4. The four general formulas for parabolas:

5. Examples

6. Assignment:
   p. 761 (3a, 4a,b, 5a,b, 7a)

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