Question 516050
{{{ sqrt( y+2 )=y }}}
square both sides
y + 2 = y^2
Arrange as a quadratic equation
0 = y^2 - y - 2
Factors to: 
(y-2)(y+1) = 0
two solutions
y = 2
y = -1
:
Check both solutions in the original problem
y=2
{{{ sqrt( 2+2 )= 2 }}}; this works
y=-1
{{{ sqrt(-1+2 )= -1 }}} this does not work, only y=2 is a solutions