[tex] \left \{ {{4x-y=11} \atop {2x+5y=11}} ight. [/tex]

4x - y = 11    /*52x + 5y = 1120x - 5y = 552x + 5y = 11 -------------------- + 22x = 66x = 3y = 4x - 11 = 4*3 - 11 = 12 - 11 = 1Ответ(3; 1)