[tex]\displaystyle\bf\\2x^{3} +x^{2} -50x-25=0\\\\(2x^{3} +x^{2}) -(50x+25)=0\\\\x^{2} (2x+1)-25(2x+1)=0\\\\(2x+1)(x^{2} -25)=0\\\\2(x+0,5)(x-5)(x+5)=0\\\\\\\left[\begin{array}{ccc}x+0,5=0\\x-5=0\\x+5=0\end{array}\right\\\\\\\left[\begin{array}{ccc}x_{1}=-0,5\\x_{2} =5\\x_{3} =-5\end{array}\right\\\\\\Otvet: \ -0,5 \ ; \ 5 \ ; \ -5[/tex]