Presentation on theme: "Warm Up Problem of the Day Lesson Presentation Lesson Quizzes."— Presentation transcript:
1 Warm UpProblem of the DayLesson PresentationLesson Quizzes
2 Warm UpSolve.1. n + 42 > 272. r + 15 < 393. –17 < w – 524. 34 < m – 19n > –15r < 2435 < w53 < m
3 Problem of the DayAracelli started riding her bike at 2 P.M. and returned home at 4 P.M. She rode less than 50 miles. What is the least her speed could have been at 3 P.M.? Explain.0 mi/h (She could have been resting or stopped at a light, for example.)3
4 Learn to solve one-step inequalities by multiplying or dividing.
6 Additional Example 1A: Solving Inequalities by Multiplying Solve.c4≤ –4c4≤ –4c4(4)≤ (–4)(4)Multiply both sides by 4.c ≤ –16
7 Additional Example 1B: Solving Inequalities by Multiplying Solve.t> 0.3–4t–4> 0.3t(–4)< (–4)0.3Multiply both sides by –4 and reverse the inequalitysymbol.–4t < –1.2
8 n 6 ≤ –5 n 6 ≤ –5 n 6 (6) ≤ (–5) (6) Multiply both sides by 6. Check It Out: Example 1ASolve.n6≤ –5n6≤ –5n6(6)≤ (–5)(6)Multiply both sides by 6.n ≤ –30
9 Multiply both sides by –3 and reverse the inequality symbol. –3 Check It Out: Example 1BSolve.r> 0.9–3r–3> 0.9r(–3)< (–3)0.9Multiply both sides by –3 and reverse the inequalitysymbol.–3r < –2.7
10 Additional Example 2A: Solving Inequalities by Dividing Solve. Check your answer.5a ≥ 235a ≥ 23Divide both sides by 5.5523535, or 4a ≥Check5a ≥ 2335?5 is greater than5(5) 23≥Substitute 5 for a.?≥
11 Additional Example 2B: Solving Inequalities by Dividing Solve. Check your answer.192< –24b192 < –24bDivide both sides by –24, and reverse the inequality symbol.–24–24–8 > bCheck192 < –24b192< –24(–10)?–10 is less than –8.Substitute –10 for b.?192 < 240
12 Check It Out: Example 2ASolve. Check your answer.6b ≥ 256b ≥ 25Divide both sides by 6.6625616, or 4b ≥Check6b ≥ 2516?6 is greater than6(6) 25≥Substitute 6 for b.?≥
13 85 < –17b 85 < –17b –17 –17 –5 > b 85 < –17b Check It Out: Example 2BSolve. Check your answer.85 < –17b85 < –17bDivide both sides by –17, and reverse the inequality symbol.–17–17–5 > bCheck85 < –17b85 < –17(–6)?–6 is less than –5.Substitute –6 for b.?85 < 102
14 Additional Example 3: Application It cost Josh $85 to make candles for the craft fair. How many candles must he sell at $4.00 each to make a profit?Since profit is the amount earned minus the amount spent, Josh needs to earn more than $85.Let c represent the number of candles that must be sold.4c > 85Write an inequality.4c > 85Divide both sides by 4.c > 21.25Josh cannot sell 0.25 candle, so he needs to sell at least 22 candles, or more than 21 candles, to earn a profit.
15 Check It Out: Example 3It cost the class $15 to make cookies for the bake sale. How many cookies must they sell at 10¢ each to make a profit?Since profit is the amount earned minus the amount spent, the class needs to earn more than $15.Let c represent the number of cookies that must be sold.0.10c > 15Write an inequality.0.10c > 15Divide both sides by .10.c > 150The class must sell more than 150 cookies to make a profit.
16 Lesson QuizzesStandard Lesson QuizLesson Quiz for Student Response Systems
17 Solve. Check each answer. 3. 18w < 4 4. –4f > 36 Lesson QuizSolve.1.2.Solve. Check each answer.3. 18w < 44. –4f > 365. It cost a candle company $51 to make a dozen candles. How many candles must it sell at $7 apiece to make a profit?s9> 12s > 108b–14> 6b < –8429w <f < –9more than 7 candles, or atleast 8 candles17
18 Lesson Quiz for Student Response Systems 1. Solve –9p > 36.A. p < 4B. p > 4C. p > –4D. p < –4
19 Lesson Quiz for Student Response Systems b–12> 62. SolveA. b < 72B. b > 72C. b > –72D. b < –72
20 Lesson Quiz for Student Response Systems 3. It costs Dorothy $315 to make cakes. How many cakes must she sell at $6 a piece to make a profit?A. at least 51B. at least 53C. at least 55D. at least 57