Wednesday, April 16, 2008
Algebra (Class 69)
Announcements
Test Friday, April 18 focusing on quadratic relationships.
Lesson Title
Trading Land
Overview
The Warm-Up for today’s class remains focused on using concepts of scale, ratio, proportion, and logical reasoning to puzzle out the locations of various places on a map. Clues today include having to deal with the speed a person is traveling!
In the lesson today we work on writing expressions to represent a situation involving the trading of land. These expressions turn out to be quadratic and we will see how we can express the area of the land in two different forms-- expanded and factored. The transforming of quadratic equations from factored to expanded form and back will turn out to be a very useful tool in the near future.
Textbook Sections
Supplemental
Connected Math: Frogs, Fleas, and Painted Cubes- Problem 2.1 Trading Land
Vocabulary
rectangle
area
perimeter
maximum
quadratic relationship
parabolas
function
symmetry
line of symmetry
x-intercepts
roots
y-intercepts
parabola
expression
factored form
expanded form
Key Attitudes
Math is about investigating and confirming
Key Ideas
Quadratic expressions can be written in expanded or factored form.
The factored form of a quadratic equation can be easily used to find the x-intercepts of the graph of that equation.
The expanded form of a quadratic equation can be easily used to find the y-intercept of the graph of that equation.
The vertex of a parabola is always located on a vertical line half-way between the x-intercepts.
Key Skills
I can enter a quadratic equation into a graphing calculator.
I can use a graphing calculator to make a table of values, including adjusting the starting value and the increment between “x” values.
I can use a table of value to find the maximum or minimum of a quadratic relationship.
I can use a table of values relating the area to the length of a side of rectangles with a fixed perimeter to determine the perimeter of the rectangle.
I can describe a graph of a quadratic equation using x-intercepts, y-intercept, location of the line of symmetry, location of the vertex, and the direction of the opening of the parabola.
I can describe the important features of a parabola (x-int, y-int., L.O.S., vertex, opens up or opens down)
I can create expressions to represent to represent the relationship between the side length and the area of a rectangle with fixed area.
Turn-In (#68)
ACE p. 11 #11-20, 26, 27
Get “Course Selection for Next Year” signed by a parent
Handouts
No Handouts Posted
Assignment
ACE p.11 #29
ACE p.30 #1
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.
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