Algebraic Expressions and the Order of OperationsAlgebraic Expressions and the Order of OperationsCOURSE 3 LESSON 1-1COURSE 3 LESSON 1-1

Evaluate the expression t + (12 – t ) ÷ 2 for t = 6.

t + (12 – t ) ÷ 2

Substitute 6 for t.= 6 + (12 – 6) ÷ 2

Work within parentheses.= 6 + 6 ÷ 2

Divide.= 6 + 3

Add.= 9

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Algebraic Expressions and the Order of OperationsAlgebraic Expressions and the Order of OperationsCOURSE 3 LESSON 1-1COURSE 3 LESSON 1-1

An Internet provider charges $25 for a connection fee, and

then $16 per month. Write an expression to model the total cost and

then evaluate the expression for 1 to 5 months of Internet access.

Expression 25 + 16 • m

Words connection fee plus 16 times number of months

Let m = the number of months.

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Algebraic Expressions and the Order of OperationsAlgebraic Expressions and the Order of OperationsCOURSE 3 LESSON 1-1COURSE 3 LESSON 1-1

(continued)

m 25 + 16m Total Cost

1 25 + 16(1) $41

2 25 + 16(2) $57

3 25 + 16(3) $73

4 25 + 16(4) $89

5 25 + 16(5) $105

Evaluate the expression for each value of the variable. Use the values 1–5 for m.

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Algebraic Expressions and the Order of OperationsAlgebraic Expressions and the Order of Operations

1. Write an expression for the number of months in y years.

2. Evaluate your expression in Exercise 1 for 7 years.

3. Evaluate 5n – n ÷ 2 for n = 10.

4. Evaluate 3c – 5 for c = 2, 4, and 6.

COURSE 3 LESSON 1-1COURSE 3 LESSON 1-1

12y

84 months

45

1, 7, 13

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