1. Lesson 2-4: Solving Multi-Step Equations Algebra 1 CP Mrs. Mongold

2. Steps to Solve Multi-Step Equations

3. 1. Combine like terms on each side of the equation

4. Steps to Solve Multi-Step Equations 1. Combine like terms on each side of the equation 2. Isolate the variable… equation should have the variable on one side and a constant on the other

5. Steps to Solve Multi-Step Equations 1. Combine like terms on each side of the equation 2. Isolate the variable… equation should have the variable on one side and a constant on the other 3. Get the variable by itself completely, remove all coefficients.

6. Steps to Solve Multi-Step Equations 1. Combine like terms on each side of the equation 2. Isolate the variable… equation should have the variable on one side and a constant on the other 3. Get the variable by itself completely, remove all coefficients. 4. CHECK your answer in the original problem…. EVERY TIME… this is not an option it’s a requirement

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22. Word Problems and Problem Solving Consecutive numbers

23. Word Problems and Problem Solving Consecutive numbers are numbers that go in numerical order, counting by 1

24. Word Problems and Problem Solving Consecutive numbers are numbers that go in numerical order, counting by 1 –Example: 1, 2, 3 and -10, -9, -8

25. Word Problems and Problem Solving Consecutive numbers are numbers that go in numerical order, counting by 1 –Example: 1, 2, 3 and -10, -9, -8 Represent these algebraically in terms of x

26. Word Problems and Problem Solving Consecutive numbers are numbers that go in numerical order, counting by 1 –Example: 1, 2, 3 and -10, -9, -8 Represent these algebraically in terms of x x, x +1, x + 2, x + 3, x + 4, ….

27. Word Problems and Problem Solving Consecutive Even Numbers:

28. Word Problems and Problem Solving Consecutive Even Numbers: numbers in numerical order that are divisible by 2 evenly

29. Word Problems and Problem Solving Consecutive Even Numbers: numbers in numerical order that are divisible by 2 evenly –Example: 2, 4, 6 and -6, -4, -2

30. Word Problems and Problem Solving Consecutive Even Numbers: numbers in numerical order that are divisible by 2 evenly –Example: 2, 4, 6 and -6, -4, -2 To represent these algebraically in term of x

31. Word Problems and Problem Solving Consecutive Even Numbers: numbers in numerical order that are divisible by 2 evenly –Example: 2, 4, 6 and -6, -4, -2 To represent these algebraically in term of x x, x + 2, x + 4, x + 6, …

32. Word Problems and Problem Solving Consecutive Odd Numbers:

33. Word Problems and Problem Solving Consecutive Odd Numbers: numbers in numerical order that are not divisible by 2

34. Word Problems and Problem Solving Consecutive Odd Numbers: numbers in numerical order that are not divisible by 2 –Example: 3, 5, 7 and -9, -7, -5

35. Word Problems and Problem Solving Consecutive Odd Numbers: numbers in numerical order that are not divisible by 2 –Example: 3, 5, 7 and -9, -7, -5 Represent these algebraically in terms of x

36. Word Problems and Problem Solving Consecutive Odd Numbers: numbers in numerical order that are not divisible by 2 –Example: 3, 5, 7 and -9, -7, -5 Represent these algebraically in terms of x x, x + 2, x + 4, x + 6, …

37. When doing word problems… 1. Define your variables 2. Write your equation 3. Solve your equation 4. Plug your answers back in to get ALL of the numbers in the problem not just x

38. Find three consecutive integers whose sum is 21

39. Define variable:

40. Find three consecutive integers whose sum is 21 Define variable: x = first of three numbers

41. Find three consecutive integers whose sum is 21 Define variable: x = first of three numbers Write an equation:

42. Find three consecutive integers whose sum is 21 Define variable: x = first of three numbers Write an equation: x + (x +1) + (x + 2) = 21

43. Find three consecutive integers whose sum is 21 Define variable: x = first of three numbers Write an equation: x + (x +1) + (x + 2) = 21 Solve:

44. Find three consecutive integers whose sum is 21 Define variable: x = first of three numbers Write an equation: x + (x +1) + (x + 2) = 21 Solve: 3x + 3 = 21

45. Find three consecutive integers whose sum is 21 Define variable: x = first of three numbers Write an equation: x + (x +1) + (x + 2) = 21 Solve: 3x + 3 = 21 -3 -3

46. Find three consecutive integers whose sum is 21 Define variable: x = first of three numbers Write an equation: x + (x +1) + (x + 2) = 21 Solve: 3x + 3 = 21 -3 -3 3x = 18

47. Find three consecutive integers whose sum is 21 Define variable: x = first of three numbers Write an equation: x + (x +1) + (x + 2) = 21 Solve: 3x + 3 = 21 -3 -3 3x = 18 3 3

48. Find three consecutive integers whose sum is 21 Define variable: x = first of three numbers Write an equation: x + (x +1) + (x + 2) = 21 Solve: 3x + 3 = 21 -3 -3 3x = 18 3 3 x = 6

49. Find three consecutive integers whose sum is 21 Define variable: x = first of three numbers Write an equation: x + (x +1) + (x + 2) = 21 Solve: 3x + 3 = 21 -3 -3 3x = 18 3 3 x = 6 PLUG BACK IN to answer the question!! The three numbers are 6, 7, and 8 CHECK 6 + 7 + 8 = 21

50. Find three consecutive even integers whose sum is -42

51. Define variable:

52. Find three consecutive even integers whose sum is -42 Define variable: x = first of the even numbers

53. Find three consecutive even integers whose sum is -42 Define variable: x = first of the even numbers Write an equation:

54. Find three consecutive even integers whose sum is -42 Define variable: x = first of the even numbers Write an equation: x + (x + 2) + (x + 4) = -42

55. Find three consecutive even integers whose sum is -42 Define variable: x = first of the even numbers Write an equation: x + (x + 2) + (x + 4) = -42 Solve: 3x + 6 = -42

56. Find three consecutive even integers whose sum is -42 Define variable: x = first of the even numbers Write an equation: x + (x + 2) + (x + 4) = -42 Solve: 3x + 6 = -42 -6 -6

57. Find three consecutive even integers whose sum is -42 Define variable: x = first of the even numbers Write an equation: x + (x + 2) + (x + 4) = -42 Solve: 3x + 6 = -42 -6 -6 3x = -48

58. Find three consecutive even integers whose sum is -42 Define variable: x = first of the even numbers Write an equation: x + (x + 2) + (x + 4) = -42 Solve: 3x + 6 = -42 -6 -6 3x = -48 3 3

59. Find three consecutive even integers whose sum is -42 Define variable: x = first of the even numbers Write an equation: x + (x + 2) + (x + 4) = -42 Solve: 3x + 6 = -42 -6 -6 3x = -48 3 3 x = -16

60. Find three consecutive even integers whose sum is -42 Define variable: x = first of the even numbers Write an equation: x + (x + 2) + (x + 4) = -42 Solve: 3x + 6 = -42 -6 -6 3x = -48 3 3 x = -16 PLUG BACK IN to answer question The three even integers are -16, -14, -12 CHECK -16 + (-14) + (-12) = -42