Đáp án: $x=\frac{145}{166}\pm\frac{5\sqrt{\frac{20783}{3}}}{166}$
Giải thích các bước giải:
$(\frac{68}{25}x^2-9)+(\frac{8}{3}-5x)=\frac{4}{5}x+3|1-(\frac{x}{5}x-3)|\\\Leftrightarrow 204x^2-375x-475=60x+225|\frac{x^2}{5}+4|\\\Leftrightarrow \frac{204x^2-435x-475}{225}=|\frac{x^2}{5}+4|\\\Leftrightarrow \frac{68}{75}x^2-\frac{29}{15}x-\frac{19}{9}=|\frac{x^2}{5}+4|\\TH1: \frac{68}{75}x^2-\frac{29}{15}x-\frac{19}{9}=\frac{x^2}{5}+4\\\Leftrightarrow 158x^2-435x-1375=0\\\Leftrightarrow \left[\begin{array}{l}x=4,63196404\\x=-1,878799483\end{array}\right.\\TH2: \frac{68}{75}x^2-\frac{29}{15}x-\frac{19}{9}=-\frac{x^2}{5}-4\\\Leftrightarrow 249x^2-435x+425=0(vô\hspace{0,1cm}nghiệm)\\\Rightarrow x=\frac{145}{166}\pm\frac{5\sqrt{\frac{20783}{3}}}{166}$
