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Math Help - Can someone help with sqrt(x-3)+sqrt(x+2)=5

  1. #1
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    Can someone help with sqrt(x-3)+sqrt(x+2)=5

    I know there are other ways to solve this, but if I keep to the rules of Algebra I should be able to solve it this way. Can anyone give me any insight on what I'm doing wrong???


    I know the answer is X=7 but 99.99% of true exams require work to prove it.

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  2. #2
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    There's an error in going from your second to third step: -3 + 2 = {\color{blue}-}1 (not +1).

    Also, make sure you change the sign when moving a term over to the other side of the equal sign. In your third last step, that should be a +4x^2 (not -).
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  3. #3
    Member kalyanram's Avatar
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    Hi,
    The actual problem is (a+b)^2 = a^2 + 2ab + b^2
    you missed out the "2" in 2ab term if you include that in your second step
    x^2 cancels out in your fourth step giving you x=7, when you solve the linear equation.

    ~Kalyan.
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  4. #4
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    Thumbs up You guys rock!

    It's these little typos and forgetful things with these kind of problems that always kill me. With your help I was able to refresh my memory.


    I appreciate everyones assistance.
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