($\frac{3}{5}$ x+2)$x^{2}$ +4 = 0
=> $\frac{3}{5}$ $x^3$+2$x^2$ = 0
=> $x^{2}$ ($\frac{3}{5}x + 2$ )= 0
=> \(\left[ \begin{array}{l}x^2=0\\\frac{3}{5}x + 2 = 0\end{array} \right.\)
=> \(\left[ \begin{array}{l}x=0\\\frac{3}{5}x = -2\end{array} \right.\)
=> \(\left[ \begin{array}{l}x=0\\\frac{3}{5}x = -2\end{array} \right.\)
=> => \(\left[ \begin{array}{l}x=0\\x =\frac{-10}{3} \end{array} \right.\)
Vậy ...
