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3x^3+2x^2-27x-18
How to solve using grouping

User Isidrok
by
3.0k points

1 Answer

3 votes

Answer:

x=3 & x=-2/3

Explanation:

  1. 3x^3+2x^2-27x-18
  2. (3x^3-27x)+(2x^2-18)
  3. 3x(x^2-9)+2(x^2-9)
  4. (3x+2)(x^2-9)
  5. 3x+2=0
  6. 3x=-2
  7. 3x/3=-2/3
  8. x=-2/3
  9. x^2-9=0
  10. x^2=9

  11. \sqrt{x^2=
    √(9)
  12. x=3
  13. x= -2/3 & x=3
User Bhargav Jhaveri
by
3.0k points