章节大纲

  • Section 4.2: Types of Systems of Equations
    ::第4.2节:等式系统类型

    Review
    ::回顾

    1. consistent, dependent; coincident
      ::一致、有依赖性; 顺数
    2. inconsistent, independent; parallel
      ::不一致、独立;平行
    3. consistent, independent; intersecting
      ::一致、独立;交叉
    4. inconsistent, independent
      ::前后不一致、独立
    5. consistent, independent
      ::一致、独立
    6. inconsistent, independent
      ::前后不一致、独立
    7. consistent, dependent
      ::一致、有受扶养人
    8. consistent, dependent
      ::一致、有受扶养人
    9. consistent, independent
      ::一致、独立
    10. consistent, independent
      ::一致、独立

    Explore More
    ::探索更多

    1. a) Answers will vary. Example: 2x + 3y = 5, 2x – 3y = 5    
      b) Answers will vary. Example: 2x + 3y = 5, 4x + 6y = 10  
      c) Answers will vary. Example: 2x + 3y = 5, 2x + 3y = -3  
      d) x = -1, y = 2 or x + 0y = -1, 0x + y = 2    
      e) Answers will vary. Example: x = -1, 2x + 2y = 2  
      f) Answers will vary. Example: 2x + 2y = 2, 2x - 2y = -6
      ::a) 答案会变化。例如:2x+3y=5,2x-3y=2,2x-3y=3,3y=5,2x-3y=5,2x+3y=5,4x+6y=10c)答复会变化。例如:2x+3y=5,2x+3y=5,2x+3d)x=-1,y=2或x+0y=1,0x+y=2e)答复会变化。例如:x=-1,2x+3y=5,4x+6y=10c)答复会变化。例子:2x+2y=2,2x-2y=6。
    2. No, if the line is the same, it will have infinite solutions (which fits at least one requirement). 
      ::否,如果线线相同,它将有无限的解决办法(至少符合一项要求)。
    3. No, there cannot be negative people (or other animals, etc.).
      ::不,不可能有负面的人(或其他动物等等)。
    4. Sonia: 2a + 3b = 4
      Muhammed: 4a + 6b = 8
      Consistent and dependent
      ::索尼娅:2a+3b=4 Muhammed:4a+6b=8
    5. Peter: D = 5t + 20
      Nadia: D = 6t
      Consistent and independent
      ::彼得:D = 5t + 20 Nadia: D = 6 一致和独立

     

    Section 4.3: Solving Systems of Equations by Graphing
    ::第4.3节:通过图表绘制的平方溶解系统

    Review
    ::回顾

    1. D, Solution: (-2, 2)
      ::D,解决方案伤心-2,2)
    2. C, Solution: (3, 0)
      ::C,解决方案伤心3,0)
    3. A, Solution: (0, 1)
      ::A,解决办法伤心0,1)
    4. B, Solution: (1, 0)
      ::B,解决方案伤心1,0)
    5. Solution: (5, -1)

      ::解决办法: (5, -1)
    6. Solution: (3, 2)

      ::解决办法伤心3,2)
    7. Solution: (-1, 3)

      ::解决办法伤心-1,3)
    8. Solution: (4, 0)

      ::解决办法: (4,0)
    9. Solution: (-2, -5)

      ::解决办法伤心-2, 5)
    10. Solution: (-3, 2.5)

      ::解决办法伤心-3,2.5)

     


    Explore More

    ::探索更多

    1. a) Bargain: $6.50 for 1 hour
          Frugal: $7.25 for 1 hour
          Bargain: $20 for 10 hours
          Frugal: $18.50 for 10 hours
      b)  y = 1.5 x + 5  for B
           y = 1.25 x + 6  for F
      c) Cost is the same at (4, 11). 4 hours for $11
      d) Bargain Bikes. It will cost $9.50 instead of $9.75.
      :伤心a) 讨价还价:6.50美元,1小时;7.25美元,1小时;20美元,10小时;18.50美元,10小时(b),y=1.5x+5美元,B=1.25x+6美元,F(c)费用不变(4,11小时,4小时,11美元)。
    2. t = 20  seconds
      D = 120  feet
      ::t=20秒 D=120英尺
    3. y = 6.6  years
      ::y=6.6岁
    4.   m = 5 1 3    
      ::m=513米=513米

    Section 4.4: Solving Systems of Equations by Substitution
    ::第4.4节:以替代方式解决等式的系统

    Review
    ::回顾

    1. (-10, 3)
    2. (0, 6)
    3. (2, -5)
    4. (8, -1)
    5. (4, 7)
    6. (13, -2)
    7. (9, 0)
    8. (-11, 9)
    9. (-3, -6)
    10. (7, 5)
    11. ( 1 2 , 1 1 3 )
    12. (1, 4)
    13. No solution
      ::无解决方案
    14. Infinite solutions
      ::无限解决方案

    Explore More
    ::探索更多


    1.  
    2. 3 shorts and 4 T-shirts
      ::3短裤和4件T恤衫
    3. 523 students
      ::523名学生
    4. A ny number of texts will solve the equation (all solutions, because the equations are dependent).
      ::任何数个文本将解答方程式(所有解决方案,因为方程式取决于方程式)。
    5.   A = 90. ¯ 90 B = 409. ¯ 09  
      ::A=90,90,B=409,09
    6. 10 pounds of each type of coffee
      ::每种咖啡10磅

    Section 4.5: Solving Systems of Equations by Addition
    ::第4.5节:通过加法解决等式的解决系统

    Review
    ::回顾

    1. (2, -7)
    2. (3, -5)
    3. (10, -11)
    4. (-6, 1)
    5. (9, 4)
    6. (-8, 2)
    7. (6, -2)
    8. (-5, 5)
    9. (4, -9)
    10. No solution
      ::无解决方案
    11. (0, 0)
    12. Infinite solutions
      ::无限解决方案

    Explore More
    ::探索更多

    1. 3 & 7
    2. x = $ 0.25  apples, y = $ 0.30  oranges 
      ::x=0.25苹果,y=0.30橙子
    3. 10 movie rentals
      ::10部电影出租
    4. w = 24  mph 
      ::W=24 英里
    5. w = $12 per warranty, h = $8.20
      ::w = 每保证金12美元,h = 8.20美元

     

    Section 4.6:    Solving Systems of Equations by Multiplication and Addition
    ::第4.6节:通过乘数和加法解决等同的解决系统

    Review
    ::回顾

    1. x = 6, y = -3 or (6, -3)
      ::x = 6, y = -3 或 (6, 3)
    2. x = -1, y = 4 or (-1, 4)
      ::x = - 1,y = 4 或 (-1, 4)
    3. x = -11, y = 5 or (-11, 5)
      ::x = -11,y = 5 或 (-11, 5)
    4. x = 7, y = 2.5 or (7, 2.5)
      ::x = 7,y = 2.5 或 (7, 2.5)
    5. x = 2, y = -10 or (2, -10)
      ::x = 2,y = -10 或 2,-10
    6. x = 48, y = 36 or (48, 36)
      ::x=48,y=36或(48,36)
    7. x = 8, y = -9 or (8, -9)
      ::x = 8,y = -9 或 (8,-9)
    8. x = -6, y = -5 or (-6, -5)
      ::x = -6, y = -5 或 (6, 5)
    9. x =  - 21 5 , y = 0 or  ( - 21 5 , 0 )  or ( - 4.2 , 0 )  
      ::x = - 215 y = 0 或 (-215,0) 或 (-4.2,0)
    10. x = 12, y = -13 or (12, -13)
      ::x = 12,y = -13 或 (12,-13)
    11. x = 1, y = 4 or (1, 4)
      ::x=1,y=4或(1,4)
    12. x = 3, y = 3.5 or (3, 3.5)
      ::x = 3,y = 3.5 或 (3,3.5)
    13. Same line, infinite solutions
      ::同一直线, 无限的解决方案
    14. x = -2, y = -11 or (-2, -11)
      ::x = -2,y = -11 或 (-2,-11)
    15. x = - 12 64 = - 3 16 , y = 1 10  or ( - 3 16 , 1 10 )  
      ::x=1264=316,y=110或(-316,110)

    Explore More
    ::探索更多

    1. A = 4.875 mL, B = 8.125 mL
      ::A=4.875毫升,B=8.125毫升
    2. $6.75
    3. $6.20
    4. $12 
    5. $5.75

     

    Section 4.7: Determining the Best Method to Use When Solving a System of Equations
    ::第4.7节:确定在解决公平制度时采用的最佳方法

    Review
    ::回顾

    1. x = 3, y = 8 or (3, 8)
      ::x = 3, y = 8 或 (3, 8)
    2. x = -5, y = -1 or (-5, -1)
      ::x = 5, y = -1 或 (5, 1)
    3. x = -2, y = 9 or (-2, 9)
      ::x = - 2,y = 9 或 (-2, 9)
    4. x = - 1 2 , y = - 1 2  or  ( - 1 2 , - 1 2 )  
      ::x=12,y=12 或 (12, 12)
    5. x = 4, y = 6 or (4, 6)
      ::x = 4,y = 6 或 (4,6)
    6. x = 3,  y = - 3 5  or  ( 3 , - 3 5 )  
      ::x = 3, y=-35 或 (3, 35)
    7. x = 2, y = 11 or (2, 11)
      ::x = 2,y = 11 或 2, 11)
    8. x = -8,  y = 2 3  or  ( - 8 , 2 3 )  
      ::x = - 8, y= 23 或 (-8, 23)
    9. Infinite solutions, same line 
      ::无穷无尽的解决办法,同行同行
    10. x = 9, y = -2. (9, -2)
      ::x=9,y =-2(9,-2)
    11. x = 0.286, y = -1 or (0.286, -1)
      ::x=0.286,y=-1或(0.286,-1)
    12. No solutions; lines are parallel
      ::否解决方案; 线条是平行的

    Explore More
    ::探索更多

    1. x = 26, y = 9; numbers are 26 & 9
      ::x = 26,y = 9;数字为 26 & 9
    2. cars = 12, vans = 15
      ::12辆面包车=15辆
    3. cappuccinos = 5, lattes = 4
      ::卡布奇诺=5,拿铁=4
    4. w = 46.875 mph
      ::w = 46.875 毫时
    5. 1 2  pint whole and  1 2  pint skim
      ::12品脱整和12品脱滑
    6. monthly pass = $100, ride when paying per ride = $2.25
      ::每月通行证 = 100美元,每次出车时乘车 = 2.25美元

     

    Section 4.8: Solving Systems of Linear Inequalities
    ::第4.8节:线性不平等的解决系统

    Review
    ::回顾

    1. a) Yes.  b) No.  c) No.  d) Yes.
      :伤心a) 是(b) 否(c) 否(d) 是。
    2. a) Yes.  b) No.  c) No.  d) No.
      :伤心a) 是(b) 否(c) 否(d) 否(c)













    Explore More
    ::探索更多




    Section 4.9: Solving Linear Systems of Three Variables
    ::第4.9节:三个变量的溶解线性系统

    Review
    ::回顾

    1. x = - 4 , y = 1 , z = 6  
      ::x=4,y=1,z=6 x=4,y=1,z=6
    2. x = 5 , y = 9 , z = - 2  
      ::x=5,y=9,z=2x5,y=9,z=2
    3. x = 2 , y = 1 , z = 2  
      ::x=2,y=1,z=2
    4. y = - 3 2 x 4 , z = 0  
      ::y=-32x-4,z=0
    5. x = - 7 , y = 5 , z = 4  
      ::x=-7,y=5,z=4
    6. x = 1 , z = - y 4  
      ::x=1,z=-y-4x=1,z=-y-4
    7. no solutions exist
      ::不存在任何解决方案
    8. y = - x 1 , z = - x 2  
      ::y=-x-1,z=-x-2
    9. x = 4 , y = - 2 , z = 1  
      ::x=4,y=2,z=1x4,y=2,z=1
    10. y = 3 x , z = 0  
      ::y=3 - x,z=0

    Explore More
    ::探索更多

    1. Swim: 1.25 hours, or 1 hour and 15 minutes
      Bike: 2 hours
      Run: 1.5 hours, or 1 hour and 30 minutes
      ::游泳:1.25小时,或1小时15分钟,Bike:2小时运行:1.5小时,或1小时30分钟
    2. Approximately: 
      43.6 bushels of wheat
      207.3 bushels of corn
      42.1 bushels of soybeans
      ::大约:小麦43.6桶