Fri 10/23 Learning Objective: To remember everything learned in Chapter 3! Lesson Hw: Chapter 3 Review WS 1 Rev Mon 10/26 Learning Objective: To remember everything learned in Chapter 3! Lesson Hw: Chapter 3 Review WS 2 Rev Tues Learning Objective: To remember everything learned in Chapter 3! 10/27 Lesson Rev Hw: Chapter 3 Review WS 3 Tues Learning Objective: To remember everything learned in Chapter 3! 10/27 Lesson Rev Hw: Quiz Correction Algebra II To remember everything in Chapter 3! 1. –4 = 4y – 2x – 2y = –x + 12 –4 = 4y – 2x +2x +2x 2x – 4 = 4y 4 4 4 y= 1 𝑥 2 −1 – 2y = –x + 12 –2 –2 –2 y= 1 𝑥 2 −6 y= 1 𝑥 2 −1 y= 1 𝑥 2 −6 No Solution Lines are Parallel & will NEVER cross! 2. –9y – 2x = 81 9y = –2x - 81 –9y – 2x = 81 + 2x +2x –9y = 2x + 81 –9 –9 –9 y= 2 − 𝑥 9 −9 9y = – 2x – 81 9 9 9 y= 2 − 𝑥 9 −9 y= 2 − 𝑥 9 −9 y= 2 − 𝑥 9 −9 Infinite Solutions SAME line will ALWAYS touch y = 2𝑥 − 9 y = −3𝑥 − 4 (1, – 7) y > −3𝑥 + 8 y < −3x − 2 No Overlap No Solution! No Shading!!! y< 1 − 𝑥 2 y< 2 𝑥 3 +1 −6 −7𝑥 + 3𝑦 = −13 6. 4𝑥 + 𝑦 = 2 4x + y = 2 -4x -4x y = -4x + 2 - 7x + 3(-4x +2) = -13 - 7x – 12x +6 = -13 4(1) + y = 2 -19x = -19 4+y=2 x=1 y=-2 (1, -2) (-2)(−4𝑥 − 8𝑦 )= −4 (-2) 8𝑥 + 16𝑦 = 8 7. −8𝑥 − 16𝑦 = −8 −8𝑥 − 16𝑦 = −8 0=0 Infinite Solutions Same Line! (-5)(−3𝑥 + 4𝑦) = −4 (-5) 15𝑥 − 20𝑦 = 20 8. (4)(7𝑥 + 5𝑦 = ) −5 (4) 28𝑥 + 20𝑦 = −20 43x = 0 x=0 (0, -1) 7(0) + 5y = –5 5y = – 5 y = –1 9. 4𝑥 + 3𝑦 + 5𝑧 = 10 𝑥 + 6𝑦 − 5𝑧 = 14 −6𝑥 − 2𝑦 + 5𝑧 = −25 4x + 3y + 5z = 10 x + 6y – 5z = 14 5x + 9y = 24 x + 6y – 5z = 14 –6x – 2y + 5z = –25 –5x + 4y = –11 9. 5𝑥 + 9𝑦 = 24 −5𝑥 + 4𝑦 = −11 13y = 13 5x + 9(1) = 24 y=1 5x + 9 = 24 5x = 15 x=3 3 + 6(1) – 5z = 14 3 + 6 – 5z = 14 9 – 5z = 14 –5z = 5 (3, 1, -1) z = –1 2𝑥 + 𝑦 + 3𝑧 = 4 5𝑦 + 3𝑧 = −8 5(-1) + 3z = -8 10. 𝑦 = −1 -5 + 3z = -8 3z = -3 z = -1 2x + (-1) + 3(-1) = 4 2x – 1 – 3 = 4 2x – 4 = 4 (4, -1, -1) 2x = 8 x = 4 11. Find the value of two numbers if their sum is 22 and their difference is 6 x + y = 22 14 + y = 22 x–y=6 y=8 2x = 28 x = 14 {8, 14} 12. On the first day of choir ticket sales, 6 adults and 7 student ticket sold for a total of $154. Choir took in $302 on the second day be selling 13 adult tickets and 12 student tickets. Find the price of an adult and a student ticket. (-12)( 6x + 7y)= 154 (-12) -72x - 84y =-1848 (7)(13x + 12y)= 302 (7) 91x + 84y = 2114 19x = 266 6(14) + 7y = 154 x = 14 84 + 7y = 154 7y = 70 y = 10 $14 for adult tix $10 for student tix 13. A stadium has 49,000 seats. Section A seats are $25, Section B seats are $20, and Section C seats are $15. The number of seats in Section A equals the total number of seats in Section B and C. Suppose the stadium takes in $1,052,000 from each sold out event, how may seats does each section hold? x + y + z = 49000 25x + 20y + 15z = 1052000 x=y+z 13. 𝑥 + 𝑦 + 𝑧 = 49000 0 (20) 𝑥 − 𝑦 − 𝑧 = (20) 25𝑥 + 20𝑦 + 15𝑧 = 1052000 x + y + z = 49000 x–y–z=0 2x = 49000 x = 24,500 20x – 20y – 20z = 0 25x + 20y + 15z = 1052000 45x – 5z = 1052000 13. 45(24500) – 5z = 1052000 1102500 – 5z = 1052000 -5z = -50500 Section A: 24,500 Section B: 14,400 z = 10,100 Section C: 10,100 24500 + y + 10100 = 49000 34600 + y = 49000 y = 14,400