[tex]\displaystyle\bf\\x^{2} -3x+m=0\\\\3x_{1} +2x_{2} =14\\\\\\Teorema \ Vieta:\\\\x_{1} +x_{2} =3\\\\\\\left \{ {{3x_{1} +2x_{2} =14} \atop {x_{1} + x_{2} =3 \ |\cdot(-2)}} \right. \\\\\\+\left \{ {{3x_{1} +2x_{2} =14} \atop {-2x_{1} -2 x_{2} =-6}} \right. \\-----------\\x_{1} =8\\\\x_{2} =3-x_{1} =3-8=-5\\\\m=x_{1} \cdot x_{2} =8\cdot(-5)=-40\\\\\\Otvet \ : \ x_{1} =8 \ \ ; \ \ x_{2} =-5 \ \ ; \ \ m=-40[/tex]