Here's the question you clicked on:

55 members online
  • 0 replying
  • 0 viewing

ligia587

  • 3 years ago

which is expression is equivalent to

  • This Question is Closed
  1. ligia587
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    if \[\sqrt{x-a}=b, x>a \]

  2. ligia587
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    which expression is equivalent to x? \[b^{2}-a \]

  3. ligia587
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    \[b-a\]

  4. ligia587
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    b+a

  5. ligia587
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    or b^2+a

  6. kirbykirby
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 1

    \[\sqrt{x-a}=b\]=>\[x-a=b^2\]=>\[x=b^2+a\]

  7. kirbykirby
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 1

    When solving with radicals, square both sides because \[(\sqrt{x})^2=x\]

  8. kirbykirby
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 1

    It will just get rid of it :)!!

  9. ligia587
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    so b^2+ a is the answer?

  10. kirbykirby
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 1

    yes

  11. ligia587
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    how did you know x=> ?

  12. kirbykirby
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 1

    Did you understand the first step? that x-a = b^2 ?

  13. ligia587
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    no i dont

  14. ligia587
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    |dw:1358391793350:dw|

  15. kirbykirby
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 1

    Ok. Do you understand why \[(\sqrt{x})^2=x\]?

  16. kirbykirby
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 1

    The "x > a" is just imposing a restriction value on your x. You don't need to use it to solve for x

  17. ligia587
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    where did you get the square from?

  18. kirbykirby
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 1

    It's what you need to do in order to solve the equation. It's similar to like when you have an equation like: \[2x-4=10\]\[2x=10+4\]\[2x=14\]\[\frac{2x}{2}=\frac{14}{2}\]\[x=7\] You could argue "how did you get the divided by 2 part?" Well it's similar to your situation. You introduce this exponent to get rid of your square root, just like you introduced a divided by 2 up here^ to isolate your x

  19. ligia587
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    ohh ok

  20. ligia587
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    thanks so much :)

  21. kirbykirby
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 1

    No problem :)

  22. ligia587
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    can you help me with another problem?

  23. kirbykirby
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 1

    SUre

  24. kirbykirby
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 1

    @ligia587

  25. ligia587
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    yea?

  26. ligia587
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    i thought you left

  27. kirbykirby
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 1

    I can help your with your question if you need

  28. kirbykirby
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 1

    you*

  29. Not the answer you are looking for?
    Search for more explanations.

    • Attachments:

Ask your own question

Sign Up
Find more explanations on OpenStudy
Privacy Policy