Identify the extraneous solution when solving √x+2= x

Answer 1

√(x+2) = x
x+2 = x^2
x^2-x-2 = 0
(x-2)(x+1) = 0
x = 2 or -1

Now just plug in the roots. -1 does not fit because √1 = 1, not -1.

-1 is the solution to -√(x+2)=x

because both the plus and minus roots when squared come out positive.