9P10: Solve quadratic equations by factoring

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6-5 Factoring

• 9P10 Solve quadratic equations by factoring

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Factor
Method 1) Guess and check What we know A
Trinomial comes from FOIL Its first term is
What are ways to factor it? The last term
is -3 What are ways to factor it? Outside
and Inside added up to 10x. Which one works?
The bigger factor must be positive because b is
( )(
) ( )(
)
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FactorMethod 2Geo Method
ac -24 B 10


The bigger factor must be positive b/c b is
4x -1
F O
I L
2x 3
Find GCF of each column and row
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Example 2
Method 1) Guess and check What we know A
Trinomial comes from FOIL Its first term is
What are ways to factor it? The last term
is 20 What are ways to factor it? Outside
and Inside added up to 31x. Which one works?
Since all coefficients are both factors have
( )(
) ( )(
) (
)( )
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Example 2Method 2 Geo Method
ac b


F O
I L
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You Try Guess and Check

• Factor

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You Try Geo Method

• Factor

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Pick Method remember to take out GCF first

• Factor

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Factor

• Prove by ac / b table!!!

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Assignment

• Day 1/6-5/279/2-24e
• Day 2/6-5/279-280/32-62 e, 69-75

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