SOLUTION: Solve the radical equation sqrt(x+5)+1=x

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Question 407824: Solve the radical equation
sqrt(x+5)+1=x
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
Solve the radical equation
sqrt%28x%2B5%29%2B1+=+x
Subtract 1 from both sides
sqrt%28x%2B5%29+=+x+-+1
:
Square both sides
x + 5 = (x-1)^2
:
FOIL (x-1)(x-1)
x + 5 = x^2 - 2x + 1
0 = x^2 - 2x - x + 1 - 5
:
A quadratic equation
x^2 - 3x - 4 = 0
factor to:
(x-4)(x+1) = 0
Two solutions
x = 4
x = -1
:
:
Check both solutions in the original equaiton
x=4
sqrt%284%2B5%29%2B1+=+4; a good solution
and
x=-1
sqrt%28-1%2B5%29%2B1+=+-1
sqrt%284%29%2B1+=+-1; not true, x=-1 is not a good solution