92 factoring using the distributive property
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Title: Factoring Using the Distributive Property
EQ: How do we factor polynomials by using the distributive property? How do we solve quadratic equations of the form
ax + bx + c?
Warm up: p. 479 #7286 even
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Factoring by using the distributive property
• You can reverse what we learned in chapter 8 to express a polynomial as the product of a monomial factor and a polynomial factor.Example:
Factored form:
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Notes cont.• Factoring involves finding the GCFExample:
• Now you write each term as the product of the GCF (divide it out)Example:
• This will give you the factored form of:
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Write each term as the product of the GCF and its remaining factors. Then use the Distributive Property to factor out the GCF.
Use the Distributive Property to factor .First, find the CGF of 15x and .
Factor each number.Circle the common prime factors.
GFC:
Rewrite each term using the GCF.Simplify remaining factors.
Distributive Property
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Factor each number.Circle the common prime factors.
Use the Distributive Property to factor.
Rewrite each term using the GCF.
Distributive PropertyAnswer: The factored form of
is
GFC: or
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Example 21b
Use the Distributive Property to factor each polynomial.a.
b.Answer:
Answer:
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Grouping to factor• If a polynomial has four or more terms it helps to group the polynomial and then factor. This means you take and split the polynomial into pairs.
HINTS for grouping:• There are four or more terms• Terms with common factors should be grouped together.• The two common factors are identical or additive inverses of each other.Example:
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Factor
Answer:
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The additive inverse property• Recognizing the polynomial as additive inverses can be VERY helpful when factoring by grouping. Additive inverses are like (x7) (7+x). You know they are additive inverses bc when you add them together the sum is 0. Parenthesis are identical except for signs! You need to pull out a negative in one of the outside numbers• Example:
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Example 23a
Factor
Group terms with common factors.
Parenthesis are identical except for signs! You need to pull out a negative in one of the outside numbers
Answer: Distributive Property
= 3a ﴾5 + b﴿ + 4 ﴾b – 5﴿ What is outside goes in one parenthesis and
what is inside goes onto another.
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Factor
Answer:
Distributive Property
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Example 23b
Factor
Answer:
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Zero product property• If the product of two factors is 0, then at least one of the two factors is 0.
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Solve an equation in factored form• Set up the two binomials so they are equal to zero and then solve for the variable.Example:
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Example 24a
Solve Then check the solutions. If , then according to the Zero Product Property either or
Original equationor Set each factor equal to zero.
Solve each equation.
Answer: The solution set is
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Example 24a
Check Substitute 2 and for x in the original equation.
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Example 24b
Solve Then check the solutions.
Answer: {3, –2}
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Solve and equation by factoring• Write the equation so it is in the form of ab=0• Then solve for x.Example:
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Example 25a
Solve Then check the solutions. Write the equation so that it is of the form
Original equation
Solve each equation.
Factor the GCF of 4y andwhich is 4y. Zero Product Propertyor
Subtract from each side.
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Example 25a
Answer: The solution set isCheck by substituting
0 and for y in the original equation.
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Example 25b
Solve
Answer:
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Practice/HW• P. 484 #3262 even