Решите систему [latex] \left \{ {5(x+2y)-3=x+5} \atop {y+4(x-3y)=50 }} \right. [/latex]

{5х+10у-3-х-5=0 {у+4х-12у-50=0 {4х+10у=8    /х(-1) {4х-11у=50 {-4х-10у=-8 {4х-11у=50 -21у=42 у=-2 4х-20=8 4х=8+20 4х=28 х=7

[latex] \left \{ {{5(x+2y)-3=x+5} \atop {y+4(x-3y)=50}} \right. \ \textless \ =\ \textgreater \ \left \{ {{5x+10y-3=x+5} \atop {y+4x-12y=50}} \right. \ \textless \ =\ \textgreater \ \left \{ {{4x+10y=8} \atop {4x-11y=50}} \right. =\ \textgreater \ \\=\ \textgreater \ \left \{ {{x= \frac{8-10y}{4} } \atop {4*\frac{8-10y}{4}-11y=50}} \right. =\ \textgreater \ \\4*\frac{8-10y}{4}-11y=50};\\8-10y-11y=50;\\-21y=42;\\y= \frac{42}{-21} =-2;\\\left \{ {{x= \frac{8-10y}{4} } \atop {y=-2}} \right.\ \textless \ =\ \textgreater \ \left \{ {{x=7} \atop {y=-2}} \right. [/latex]