Math Lesson­2.notebook
January 29, 2015
Daily Objective
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Students will learn the steps for multiplying and dividing rational expressions by using operations similar to multiplication and division of rational numbers.
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Math Lesson­2.notebook
8.4 Multiply & Divide Rational Expressions
Day 2
January 29, 2015
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Ex. 2:
A company makes a tin to hold flavored popcorn. The tin is a rectangular prism with a square base. The company is designing a new tin with the same base and twice the height of the old tin.
~ Find the surface area & volume of each tin.
~ Calculate the ratio of surface area to volume for each tin.
~ What do the ratios tell you about the efficiencies of the two tins.
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Math Lesson­2.notebook
January 29, 2015
YOU PRACTICE
In ex. 2, suppose the new popcorn tin is the same height as the old tin but has a base with sides twice as long. What is the ratio of surface area to volume for this tin?
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Math Lesson­2.notebook
January 29, 2015
REVIEW
Ex. 3: Simplify 8x3y 7x4y3
2xy2 4y
Ex. 5: Multiply x + 2 (x2 + 3x + 9)
x3 ­ 27
Ex. 7: Divide 6x2 + x ­ 15 ÷ (3x2 + 5x)
4x2
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Math Lesson­2.notebook
January 29, 2015
8.4 HW Quiz
Multiply or divide the following expression. Simplify your answers.
1. x(x ­ 3) (x + 3)(x ­ 2)
x ­ 2 x
2. x2 ­ 3x ­ 10 (x2 + 10x + 21)
x2 ­ 2x ­ 15
3. x2 ­ 4x ­ 5 (x2 + 6x + 5)
÷
x + 5
4. x2 + 12x + 32 x2 + 4x
÷
6x + 42 x2 ­ 49
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Math Lesson­2.notebook
January 29, 2015
8.4 HW Quiz Today!
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