SELF STUDY GUIDE FOR GRADE 02/SMART TERM 02/2020 CHAPTER 09: EQUATIONS AND INEQUALITIES I. Solve the following linear equations 1. 𝑥 + 14 = 35 Answers: 1. 𝑥 = 21 2. 𝑦 = 6 3. 𝑞 = 8 4. 𝑚 = 4 5. 𝑑 = 8 2. 4𝑦 − 3 = 21 3. 5𝑞 = 4𝑞 + 8 4. 4(𝑚 − 6) = −8 5. 2(2𝑑 − 1) = 3(𝑑 + 2) Answers: 1) 2 II. 2) 5 3) 5 4)4 Construct an equation and solve the equation. 1. I think of a number, add 2 and multiply this by 3. The answer is 12. What is the number? 2. I put the same number of chocolate buttons on each of seven cakes. I had 40 buttons at the start and now have five buttons left over. How many buttons did I put on each cake? 3. A number is subtracted from 7. The results multiplied by 3 and the answer is 6. What is the number. 4. 9 times a number has 1 subtracted from it. The result is trebled. The answer is same if you add 7 to twice the number and multiply the result by 7. What is the number? III. Solve each pair of simultaneous equations by elimination. 1. 𝑚 + 𝑛 = 7 5. 2𝑙 − 𝑚 = −1 Answers: 4𝑚 − 𝑛 = 23 2𝑙 + 3𝑚 = 11 1. 𝑚 = 6, 𝑛 = 1 2. 𝑒 + 𝑓 = 5 4𝑒 − 𝑓 = 5 3. 3𝑝 + 2𝑞 = 14 5𝑝 − 2𝑞 = 2 4. 𝑔 + ℎ = 3 𝑔 + 3ℎ = 7 2. 𝑒 = 2, 𝑓 = 3 6. 3𝑟 − 𝑠 = −1 3𝑟 − 2𝑠 = −8 Answers: 5. 𝑙 = 1, 𝑚 = 3 6. 𝑟 = 2, 𝑠 = 7 3. 𝑝 = 2, 𝑞 = 4 7. 𝑟 + 2𝑠 = 0 3𝑟 − 𝑠 = −7 7. 𝑟 = −2, 𝑠 = 1 4. 𝑔 = 1, ℎ = 2 8. 3𝑚 − 4𝑛 = −14 2𝑚 + 2𝑛 = 14 8. 𝑚 = 2, 𝑛 = 5 9. The sum of two number is 12, and their difference is 8. Form two equations and solve them to find the two numbers. IV. Write the inequalities in words. 1. 𝑥 ≥ 6 2. 𝑦 < 5 3. 3 < 𝑒 ≤ 6 4. 4 > 𝑗 ≥ 0 V. Show each of these inequalities on a number line. 1. 𝑚 ≥ −1 2. 7 < 𝑓 3. 5 ≥ 𝑟 ≥ 2 4. −2 ≤ 𝑖 < 2 5. 5 ≥ ℎ > −4 VI. Write the inequality shown by each of the following number lines, using the given letter for the unknown. 1. 𝑎 2. 𝑏 3. 𝑐 VII. Solve the following inequalities 1. 𝑥 + 3 > 2 2. 3𝑥 + 2 > 5 3. 6𝑥 + 4 ≥ 5𝑥 4. 3𝑦 − 4 < 5𝑦 + 2 Answers: 1) 𝑥 > −1 2) 𝑥 > 1 3) 𝑥 ≥ −4 4) 𝑦 > −3 5) 1 < 𝑥 ≤ 6 5. 3 < 𝑥 + 2 ≤ 6 6. 8 < 2(𝑥 − 4) ≤ 10 7. 6 ≥ 2(𝑥 + 1) > 12 6) 8 < 𝑥 ≤ 9 7) 2 > 𝑥 > 5