5.8 Quadratic Formula 2010
December 10, 2010
5­8 Quadratic Formula
Objective:
Solve quadratic equations
using the quadratic formula.
Dec 4­5:56 PM
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5.8 Quadratic Formula 2010
December 10, 2010
REVIEW
How do you solve for x in each of these forms of a quadratic equation?
Standard Form
y = ax2 + bx + c Vertex Form
y = a(x ­ h)2 + k
Square Root Method
(also called isolating the square)
Factor (and use the zero product rule)
Quadratic Formula
(Today's Lesson!)
Dec 4­6:06 PM
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5.8 Quadratic Formula 2010
December 10, 2010
So....what is the quadratic formula?
A long time ago, in a country far, far away........there was a Hindu mathematician named Brahmagupta. This brave soul took the equation ax2 + bx + c = 0 and solved the equation for x. Note: There were many other mathematicians that solved this equation as well.
It goes like this:
Dec 4­6:09 PM
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5.8 Quadratic Formula 2010
December 10, 2010
Dec 4­6:11 PM
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5.8 Quadratic Formula 2010
December 10, 2010
Use the Quadratic Formula to solve 3x2 ­ 5x = 2.
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5.8 Quadratic Formula 2010
December 10, 2010
Use the Quadratic Formula to solve Dec 4­6:47 PM
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5.8 Quadratic Formula 2010
December 10, 2010
Use the Quadratic Formula to find COMPLEX solutions:
2x2 = ­6x ­ 7
Dec 4­6:50 PM
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5.8 Quadratic Formula 2010
December 10, 2010
Use the Quadratic Formula to find COMPLEX solutions:
­2x2 = 4x + 3
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5.8 Quadratic Formula 2010
December 10, 2010
HOMEWORK
p. 293 #2­20 even, 42­50 even
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