Course 1

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

2. Learn to translate between algebraic expressions and word phrases.

3. Expression Word Phrases + –  a  or a 7 7 • a number plus 5 • add 5 to a number n + 5 • 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 x 11 • 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 3m • product of 3 and a number • a number divided by 7 • 7 divided into a number • quotient of a number and 7

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

5. f 6 Check It Out: Example 1 Write an algebraic expression for each word phrase. A. the sum of a number h and 88 minus 4 the sum ofh and 88 minus 4 h+ 88 – 4 h + 88 – 4 B. the quotient of a number f and 6 quotient off and 6 f 6

6. Additional Example 2: Translating Math Expressions into Word Phrases Write a word phrase for the algebraic expression 9 – 3c. 9 – 3c 9 – 3 •c 9 minusthe product of 3 and c 9 minus the product of 3 and c.

7. Check It Out: Example 2 Write a word phrase for the algebraic expression 7 + 19b. 7 + 19b 7 + 19 •b 7 plusthe product of 19 and b 7 plus the product of 19 and b.

8. Operation Possible Question Clues Action To solve a word problem, you must first interpret the action you need to perform and then choose the correct operation for that action. Combine Add How many all together? Combine equal groups How many all together? Multiply Separate Subtract How many more? How many less? Separate into equal groups How many equal groups? Divide

9. n $10 • n Cost Additional Example 3: Writing and Evaluating Expressions in Word Problems 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 $10 dollars •n Combine n equal amounts of $10. $10n In dollars Evaluate for n = 20, 21, 22, and 23. 20$10 • 20 $200 21$10 • 21 $210 22$10 • 22 $220 23$10 • 23 $230

10. n $1.99 •n Cost Check It Out: Example 3 Gasoline costs $1.99 per n gallons. What will the cost be for 10, 12, 14, and 15 gallons? $1.99 •n Combine n equal amounts of $1.99. $1.99n In dollars 10$1.99 •10 $19.90 Evaluate for n = 10, 12, 14, and 15. 12 $1.99 •12 $23.88 14$1.99 •14 $27.86 15$1.99 •15 $29.85

11. Additional Example 4: Writing a Word Problem from a Math Expression Write a word problem that can be evaluated by the algebraic expression 27 + t, and evaluate the expression for t = 1.76. Possible Answer: Brandy 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.

12. Check It Out: Example 4 Write a word problem that can be evaluated by the algebraic expression 43 - d, and evaluate the expression for d = 10.24. 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.

13. x 11 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. 4times 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