7x^2-5x=y система 7x-5=y

[latex] \left \{ {{7x^2-5x=y} \atop {7x-5=y} \right. \\\left \{ {{7x^2-5x=7x-5} \atop {7x-5=y} \right \\ 7x^2-5x=7x-5 \\ 7x^2-12x+5=0 \\ D=12^2-4*7*5=144-140=4 \\ x_1= \frac{12+2}{2*7}=1 \\ x_2= \frac{12-2}{2*7}= \frac{10}{14}= \frac{5}{7} \\ \left \{ {{x_1=1} \atop {y_1=7*1-5=2}} \right. \\ \left \{ {{x_2= \frac{5}{7} } \atop {y_2=7* \frac{5}{7} -5=0}} \right. [/latex] два решения системы [latex](1;2)[/latex] и [latex]( \frac{5}{7};0)[/latex]