5х+3у=11 7х+17у=-23 помогите решить

[latex] \left \{ {{5x+3y=11|*7} \atop {7x+17y=-23|*(-5)}} \right. [/latex] [latex] \left \{ {{35x+21y=77} \atop {-35x-85y=115}} \right. [/latex] __________________ -64y=192 y=-3 [latex] \left \{ {{5x-9=11} \atop {y=-3}} \right. [/latex] [latex] \left \{ {{x=4} \atop {y=-3}} \right. [/latex]