Algebra
posted by Betty on .
Solve algebraically and check your potential solutions: sqrt((x+2) x =0

√x+2  x = 0
√x+2 = x
x+2 = x^2
x^2  x  2 = 0
(x2)(x+1) = 0
check for validity
√(2+2)  2 = 22 = 0 ok
√(1+2)  (1) = 1  (1) = 2 nope
Note that if you had taken the minus √, it would have been ok. But √4 does not mean ±2  it's just 2.