pre-calculus

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Could someone please help me with this problem?
square root of (2x+1) -5 = 8
I think I take the 5 and add it to the 8 and then I have
square root of (2x+1) = 13
then do I square both sides and end up with 2x+1 = 13^2
2x+1=169
2x+1-1=169-1
2x=168
x=84 am I even close on this?

  • pre-calculus -

    The best way to check is to substitute your answer back into the equation.
    SQRT(2x+1)-5=8
    SQRT( (2*84)+1)-5=8
    SQRT(168+1)-5=8
    SQRT(169)-5=8
    13 - 5 = 8
    8 = 8
    You are correct!

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