Răspuns:
Explicație pas cu pas:
[tex]\left \{ {{x+2y=10} \atop {2x-y=5}} \right.[/tex] [tex]\left \{ {{x=10-2y} \atop {2x-y=5}} \right.[/tex] [tex]\left \{ {{x=10-2y} \atop {2(10-2y)-y=5}} \right.[/tex] [tex]\left \{ {{x=10-2y} \atop {20-4y-y=5}} \right.[/tex] [tex]\left \{ {{x=10-2y} \atop {-5y=-15}} \right.[/tex] [tex]\left \{ {{x=10-2y} \atop {y=\frac{-15}{-5} }} \right.[/tex]
[tex]\left \{ {{x=10-2y} \atop {y=3}} \right.[/tex] [tex]\left \{ {{x=10-2*3} \atop {y=3}} \right.[/tex] [tex]\left \{ {{x=4} \atop {y=3}} \right.[/tex]
[tex]\left \{ {{x+y=3} \atop {x-y=2}} \right.[/tex] [tex]\left \{ {{x=3-y} \atop {x-y=2}} \right.[/tex] [tex]\left \{ {{x=3-y} \atop {3-y-y=2}} \right.[/tex] [tex]\left \{ {{x=3-y} \atop {-2y=-1}} \right.[/tex] [tex]\left \{ {{x=3-y} \atop {y=\frac{1}{2} }} \right.[/tex] [tex]\left \{ {{x=3-\frac{1}{2} } \atop {y=\frac{1}{2} }} \right.[/tex] [tex]\left \{ {{x=\frac{5}{2} } \atop {y=\frac{1}{2} }} \right.[/tex]
