Có: \(\left(x+2\right)^2-x+4=0\)
\(\rightarrow x^2+4x+4-x+4=0\)
\(\rightarrow x^2+3x+8=0\)
\(\rightarrow x^2+2x.1,5+1,5^2+5,75=0\)
\(\rightarrow\left(x+1,5\right)^2+5,75=0\)
Mà\(\left(x+1,5\right)^2\ge0,\forall x\rightarrow\left(x+1,5\right)^2+5,75\ge5,75,\forall x\)
Vậy \(x\in\varnothing\)