Question

ПОМОГИТЕ ПОЖАЛУЙСТА

Answer 1

$\left \{ {{x+5y=6} \atop {2x+3y=5}} \right.\\\\\left \{ {{x=6-5y} \atop {2*(6-5y)+3y=5}} \right. \\\\\left \{ {{x=6-5y} \atop {12-10y+3y=5}} \right.\\\\\left \{ {{x=6-5y} \atop {-7y=-7}} \right.\\\\\left \{ {{y=1} \atop {x=6-5*1}} \right.\\\\\left \{ {{y=1} \atop {x=1}} \right.\\\\Otvet:\boxed{(1;1)}$

$\left \{ {{3x-y=-1}|*3 \atop {-2x+3y=-11}} \right.\\\\+\left \{ {{9x-3y=-3} \atop {-2x+3y=-11}} \right.\\--------\\ 7x=-14\\\\x=-2\\\\y=3x+1=3*(-2)+1=-6+1=-5\\\\y=-5\\\\Otvet:\boxed{(-2;-5)}$

$\left \{ {{12x-5y=7}|*3 \atop {11x+3y=14}|*5} \right.\\\\+\left \{ {{36x-15y=21} \atop {55x+15y=70}} \right.\\ -------\\91x=91\\\\x=1\\\\3y=14-11x=14-11*1=14-11=3\\\\y=1\\\\Otvet:\boxed{(1;1)}$