Download Expanding Binomials: FOIL

Expanding Binomials: FOIL
Alex Haywood
Steven Prentice
Review of Yesterday
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Multiplicative Identity:
The product of any number and one is that number.
 (a * 1) = a and (1 * a) = a.
 Example: (5 * 1) = 5 and (1 * 5) = 5
Commutative Property:
 When two numbers are multiplied together, the
product is the same regardless of the order of the
multiplicands.
 (a * b) = (b * a)
 Example: (2 * 4) = 8 = (4 * 2)
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Review of Yesterday
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Associative Property:
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When three or more numbers are multiplied, the product is
the same regardless of the grouping of the factors.
(a * b) * c = a * (b * c)
Example: (2 * 3) * 4 = 24 = 2 * (3 * 4)
Distributive Property:
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The sum of two numbers times a third number is equal to the
sum of each addend times the third number.
a * (b + c) = (a * b) + (a * c)
(b + c) * a = (b * a) + (c * a)
Example: 2 * (3 + 4) = (2 * 3) + (2 * 4) = 6 + 8 = 14
FOIL
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Objective: By the end of the lesson the students will be
able to apply the FOIL method to simple Binomial
expressions.
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WARM UP:
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Expand: 3 * (x + 1)
Expand: x * (x + 2)
Expand: (x + 2)(x + 3)
What is FOIL?
Problem: Expand (x+4)(x+6).
 First Terms:
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Outer Terms:
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(x+4)(x+6)
Inner Terms:
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(x+4)(x+6)
(x+4)(x+6)
Last Terms:
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(x+4)(x+6)
FOIL Practice
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Expand (x + 2)(x + 1)
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Expand (x + 5)(x – 3)
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Expand (2x – 2)(x + 1)
FOIL Practice 2.0