Odpowiedź:
[tex]\left \{ {{2x+y=1} \atop {-3x+3y=9}} \right.[/tex]
[tex]\left \{ {{y=1-2x} \atop {-3x+3*(1-2x)=9}} \right.[/tex]
[tex]\left \{ {{y=1-2x} \atop {-3x+3-6x=9}} \right.[/tex]
[tex]\left \{ {{y=1-2x} \atop {-9x=6/:(-9)}} \right.[/tex]
[tex]\left \{ {{y=1-2x} \atop {y=-\frac{2}{3} }} \right.[/tex]
[tex]\left \{ {{y=1-2*(-\frac{2}{3})} \atop {x=-\frac{2}{3}}} \right.[/tex]
[tex]\left \{ {{y=1+\frac{4}{3}} \atop {x=-\frac{2}{3}}} \right.[/tex]
[tex]\left \{ {{y=\frac{7}{3} } \atop {x=-\frac{2}{3}}} \right.[/tex]
[tex]\left \{ {{2*(-\frac{2}{3})+\frac{7}{3} =1} \atop {-3*(-\frac{2}{3})+3*\frac{7}{3} =9}} \right.[/tex]
[tex]\left \{ {{-\frac{4}{3}+\frac{7}{3}=1} \atop {\frac{6}{3}+\frac{21}{3}=9}} \right.[/tex]
[tex]\left \{ {{1=1} \atop {9=9}} \right.[/tex]
Szczegółowe wyjaśnienie:
