Wednesday, April 30, 2008
Algebra (Class 74)
Announcements
Test Friday, April 18 focusing on quadratic relationships.
Lesson Title
Quadratic Formula
Overview
In today’s class the we finish the “Block Balance” series of warm-ups which have dealt with solving systems of linear equations. Our lesson for the day reviews factoring quadratic expressions and introduces the quadratic formula as a tool for factoring quadratic expressions and finding the location of the x-intercepts.
Textbook Sections
12-3 (Txt. p.567) The Quadratic Formula
Vocabulary
rectangle
area
perimeter
maximum
quadratic relationship
parabolas
function
symmetry
line of symmetry
x-intercepts
roots
y-intercepts
parabola
expression
factored form
expanded form
standard form of a quadratic equation
quadratic formula
Key Attitudes
Math is about investigating and confirming
Key Ideas
Quadratic expressions can be written in expanded or factored form.
An expression is written in expanded form when the expression is the sum or difference of terms.
An expression is written in factored form when the expression is the product of factors.
Quadratic equations written in expanded or factored form contain clues that can be used to create a graph of the equation.
The x-intercepts, line of symmetry, vertex, (and y-intercept) determine a the graph of a quadratic equation (a parabola)
The quadratic formula is a tool that can be used for finding the x-intercepts of a quadratic equation when the equation can not be factored.
Key Skills
I can change a quadratic equation from factored form to expanded form, or from expanded form to factored form.
I can find the x-intercepts from a quadratic equation written in factored form.
I can find the y-intercept of a graph of a quadratic equation when given a quadratic equation.
I can find the line of symmetry of a graph of a quadratic equation when given a quadratic equation.
I can find the vertex of a graph of a quadratic equation when given a quadratic equation.
I can match a graph of a quadratic equation to its equation written in expanded or factored form.
I can write a quadratic expression in standard form.
I can find the value of the discriminant (b^2-4ac).
I can use the quadratic formula to factor and find the x-intercepts of a quadratic equation.
Turn-In (#73)
ACE p.30 #30-33, 40, 44-47
Handouts/ Links
Using the Quadratic Formula Video 1
Using the Quadratic Formula Video 2
Using the Quadratic Formula Video 3
Assignment
Finish Worksheet 10.5 Practice B #1-33
Finish Worksheet 9.5 Practice A #1-27
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.
Permalink