Do Now 10/1/09Do Now 10/1/09

Take out HW from last night.Take out HW from last night. Text p.66, #16-26 even, 28-31 all, 32- 46 evensText p.66, #16-26 even, 28-31 all, 32- 46 evens

Copy HW in your planner.Copy HW in your planner. Text p.81, #10-21 all, #33-35 allText p.81, #10-21 all, #33-35 all

In your journal, define the word “collect”. In your journal, define the word “collect”. Do you “collect” anything? If so what?Do you “collect” anything? If so what?

HomeworkHomeworkText p.66, #16-26 even, 28-31 all, 32- Text p.66, #16-26 even, 28-31 all, 32-

46 evens46 evens

16) 5616) 56 18) 718) 7 20) -18020) -180 22) 422) 4 24) x + 2924) x + 29 26) -48c26) -48c 28) identity property of 28) identity property of

additionaddition 29)commutative 29)commutative

property of property of multiplicationmultiplication

30) associative property 30) associative property of additionof addition

31) identity property of 31) identity property of multiplicationmultiplication

32) 21,120 ft32) 21,120 ft 34) 6 minutes34) 6 minutes 36) 308 Calories36) 308 Calories 38) 220,000 lb38) 220,000 lb 40) No. You must 40) No. You must

always put on your always put on your socks before your shoessocks before your shoes

42) 11042) 110 44) 30044) 300 46) 2746) 27

Objective Objective

SWBAT simplify variable expressionsSWBAT simplify variable expressions

Parts of an ExpressionParts of an Expression

-3x + 2x + 8-3x + 2x + 8TermsTerms of the expression are separated by addition signs

CoefficientCoefficient the number part of a variable term

ConstantConstant term that has no variable

Section 2.3 “Simplifying Variable Section 2.3 “Simplifying Variable Expressions”Expressions”

Simplifying an Simplifying an ExpressionExpression

-3x + 2x + 8-3x + 2x + 8

Like TermsLike Terms terms that have The same variable

You can simplify an expression by

COLLECTING LIKE COLLECTING LIKE TERMSTERMS

--3x3x + + 2x2x + 8 + 8

-1x-1x + 8 + 8

Simplifying an ExpressionSimplifying an Expression

Write Write expression as a expression as a sumsum““Opp-Opp”Opp-Opp”

COLLECT LIKE COLLECT LIKE TERMSTERMS

4n – 7 – n + 94n – 7 – n + 9

3n3n + + 22

4n + (-7) + (-1n) + 94n + (-7) + (-1n) + 9

4n4n + + (-1n)(-1n) + + (-7)(-7) + + 99 Commutative Commutative PropertyProperty

4n – 7 – 1n + 94n – 7 – 1n + 9The coefficient is The coefficient is always 1 for a always 1 for a variable with no variable with no number in front of it.number in front of it.

Parts of an Parts of an ExpressionExpression

7x² + 5x + 8 + 3x7x² + 5x + 8 + 3x

1) List the terms of the expression. 1) List the terms of the expression.

2) List the coefficients of the expression. 2) List the coefficients of the expression. 3) List the like terms of the expression. 3) List the like terms of the expression.

4) List the constant terms of the expression. 4) List the constant terms of the expression. 5) Simplify the expression. 5) Simplify the expression.

7x², 5x, 8, 3x 7x², 5x, 8, 3x 7, 5, 3. 7, 5, 3.

5x and 3x 5x and 3x 8 8

7x² + 8x + 8 7x² + 8x + 8

Simplify the Expression Simplify the Expression

A.A. 3a + 2b + 7a3a + 2b + 7a

B.B. 5b5b²² + 7 + 10b + 7 + 10b²²

C.C. 2x – 7 + 16 – 2x – 7 + 16 – 3x 3x

D. D. x + y – 12y – x + y – 12y – 3x3x

A). 10a + 2bA). 10a + 2b

B). 15bB). 15b²² + 7 + 7

C). -x + 9 or C). -x + 9 or

-1x + 9-1x + 9

D). -2x + (-11y) orD). -2x + (-11y) or

-2x – 11y-2x – 11y

Simplifying Expressions in Simplifying Expressions in GeometryGeometry

What is the perimeter of the What is the perimeter of the trapezoid?trapezoid?

3x3x

5x5x

x + 2x + 2 x + 2x + 2

Perimeter is thePerimeter is thedistance around a figure.distance around a figure.

x + 2 + 3x + x + 2 + 5xx + 2 + 3x + x + 2 + 5x (reorder terms)(reorder terms)

Add together each of the sides.Add together each of the sides.

x + 3x + x + 5x + 2 + 2x + 3x + x + 5x + 2 + 2(combine like terms)(combine like terms)

10x + 410x + 4

Find the Perimeter of the Find the Perimeter of the FigureFigure

4 + 2w 4 + 2w

ww

Perimeter = 2(L) + 2(W)Perimeter = 2(L) + 2(W)

Perimeter = 2(w) + 2(4 +2w)Perimeter = 2(w) + 2(4 +2w)

Perimeter = 2w + 8 + 4w)Perimeter = 2w + 8 + 4w) = 6w + 8= 6w + 8

Area = length x widthArea = length x width

Area = (w)(4 + 2w)Area = (w)(4 + 2w)

Area = 4w + 2wArea = 4w + 2w²²

ChallengeChallengeWhat is the area of the figure?What is the area of the figure?

HomeworkHomework

- Text p.81, #10-21 all, #33-35 all- Text p.81, #10-21 all, #33-35 all

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