SOLUTION: help on this please,,thanks x+1= sqrt x+7

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Question 60848: help on this please,,thanks
x+1= sqrt x+7

Found 2 solutions by jai_kos, ikleyn:
Answer by jai_kos(139) About Me  (Show Source):
You can put this solution on YOUR website!
x+1= sqrt x+7
Square on both sides, we get
(x+1)^2 = x +7
x^2 + x + 1 = x + 7
Get all the numbers on one side and “x” to the other side
x^2 + x – x = 7 -1
x^2 = 6
Take the sqrt of the equation, we get
x = sqrt(6)
Hence the value of “x” = sqrt(6)

Answer by ikleyn(53742) About Me  (Show Source):
You can put this solution on YOUR website!
.
help on this please,, thanks
x+1= sqrt(x+7)
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        The solution in the post by @jai_kos is incorrect.
        See my correct solution below.


x+1= sqrt(x+7)

Square on both sides, we get

(x+1)^2 = x +7
x^2 + 2x + 1 = x + 7

Reduce it to the standard form quadratic equation

x^2 + x - 6 = 0

Factor left side

(x+3)*(x-2) = 0

The roots of this equation are x = -3 and x = 2.
Direct check shows that x = 2 is the solution to the original equation, while x = -3 is an EXTRANEOUS solution.


ANSWER. The given equation has a unique solution in real numbers x = 2.


Solved correctly.