1. Course 3 1-2 Algebraic Expressions Course 1 1-2 Algebraic Expressions Course 3 Warm Up Warm Up Problem of the Day Problem of the Day Lesson Presentation Lesson Presentation

2. Course 3 1-2 Algebraic Expressions Warm Up Evaluate each expression for the given values of the variables. Which operation symbol goes with each word? 23 18 1 +    4. Sum 5. Product 6. Quotient 7. Difference 1. 9y  13 for y = 4 2. 6n + 2p for n = 2 and p = 3 3. 3x  y for x = 1 and y = 2

3. Course 3 1-2 Algebraic Expressions Problem of the Day Find a pair of numbers that fits the description. Their product is 221 and their sum is 30. 13, 17

4. Course 3 1-2 Algebraic Expressions Learn to translate between algebraic expressions and word phrases.

5. Course 3 1-2 Algebraic Expressions a number plus 5 add 5 to a number sum of a number and 5 5 more than a number a number increased by 5 a number minus 11 subtract 11 from a number difference of a number and 11 11 less than a number a number decreased by 11 3 times a number 3 multiplied by a number product of 3 and a number a number divided by 7 7 divided into a number quotient of a number and 7 + –   Word Phrases Expression n + 5 x  11 3m3m or a  7 a 7

6. Course 3 1-2 Algebraic Expressions Write an algebraic expression for each word phrase. Additional Examples 1: Translating Word Phrases into Math Expressions A. 9 less than a number w 9 less than a number w w – 9 B. 3 increased by the difference of p and 5 3 increased by the difference of p and 5 3 + (p – 5) 3 + p – 5

7. Course 3 1-2 Algebraic Expressions Write an algebraic expression for each word phrase. Check It Out: Example 1 A. the sum of a number h and 88 minus 4 the sum of h and 88 minus 4 h + 88 – 4 B. the quotient of a number f and 6 quotient of f and 6 f  6 f 6

8. Course 3 1-2 Algebraic Expressions Write a word phrase for the algebraic expression 9 – 3c. Additional Example 2: Translating Math Expressions into Word Phrases 9 – 3c 9 minus the product of 3 and c 9 minus the product of 3 and c.

9. Course 3 1-2 Algebraic Expressions Check It Out: Example 2 Write a word phrase for the algebraic expression 7 + 19b. 7 + 19b 7 plus the product of 19 and b 7 plus the product of 19 and b.

10. Course 3 1-2 Algebraic Expressions To solve a word problem, you must first interpret the action you need to perform and then choose the correct operation for that action. Separate into equal groups Multiply How many more? How many less? Combine Combine equal groups Separate Add Subtract Divide Action OperationPossible Question Clues How many all together? How many equal groups?

11. Course 3 1-2 Algebraic Expressions A restaurant leased its banquet hall for a function. The cost was $10 per person. Write an algebraic expression to evaluate what the cost would be if 20, 21, 22, or 23 people attended the function Additional Example 3: Writing and Evaluating Expressions in Word Problems $10 dollars nCombine n equal amounts of $10. $10nIn dollars 20 $10 20 $200 21 $10 21 $210 22 $10 22 $220 23 $10 23 $230 n $10 n Cost Evaluate for n = 20, 21, 22, and 23.

12. Course 3 1-2 Algebraic Expressions Gasoline costs $1.99 per n gallons. What will the cost be for 10, 12, 14, and 15 gallons? Check It Out: Example 3 $1.99 nCombine n equal amounts of $1.99. $1.99nIn dollars 10 $1.99 10 $19.90 12 $1.99 12 $23.88 14 $1.99 14 $27.86 15 $1.99 15 $29.85 n $1.99 n Cost Evaluate for n = 10, 12, 14, and 15.

13. Course 3 1-2 Algebraic Expressions Write a word problem that can be evaluated by the algebraic expression 27 + t, and evaluate the expression for t = 1.76. Additional Example 4: Writing a Word Problem from a Math Expression Possible Answer: Amed bought a new sweater for $27 plus sales tax t. If the tax was $1.76, what was the total cost of the sweater? 27 + t 27 + 1.76 = 28.76 Substitute 1.76 for t. The total cost of the sweater was $28.76.

14. Course 3 1-2 Algebraic Expressions Write a word problem that can be evaluated by the algebraic expression 43 - d, and evaluate the expression for d = 10.24. Check It Out: Example 4 Possible Answer: Tina bought a new jacket for $43 minus a store credit. If the store credit was $10.24, what was the total cost of the jacket? 43 + d 43 – 10.24 = 33.24 Substitute 10.24 for t. The total cost of the jacket was $33.24.

15. Course 3 1-2 Algebraic Expressions Lesson Quiz Write an algebraic expression for each word phrase. 1. 5 less than a number k 2. a number x divided by 11 3. 4 times the sum of n and 5 Write an algebraic expression to evaluate the word problem. 4. Karen buys n raffle tickets for $0.50 each. If she buys 13 of them, how much will they cost? k – 5 4(n + 5) 0.50n; $6.50 x 11