[latex]7 a^{2} [/latex]+4a-3=0D=[latex]b^{2} [/latex]-4acD=16+84=100[latex] x_{1} [/latex]=[latex] frac{-b+ sqrt{D} }{2a} [/latex]=[latex] frac{-4+10}{7*2} [/latex]=[latex] frac{6}{14} [/latex]=[latex] frac{3}{7} [/latex][latex] x_{2} = frac{-b- sqrt{D} }{2a} = frac{-4-10}{14} =-1[/latex]

D=b^2-4acD= 16-4*7*(-3)D=16-(-84)=100x1,2= -b+/-корень из 100х1= -4+10/2*7=6/14х1=3/7х2=-4-10/14=-1Ответ: 3/7;  -1