Question

Решите систему

Если xy=a, y/x=b

Answer 1

Ответ:(3,-3);(-3,3)

Объяснение:

$\left \{ {{a+b=-10} \atop {5b=13+2a}} \right. \\\left \{ {{a+b=-10} \atop {5b-2a=13}} \right. \\\left \{ {{a+b=-10} \atop {-2a+5b=13}} \right. \\\\\left \{ {{2a+2b=-20} \atop {-2a+5b=13}} \right. \\\\a=-9 , b=-1\\\left \{ {{xy=-9} \atop {\frac{y}{x} =-1}} \right. \\y=-x\\xy=-9 === > x*(-x)=-9 === > x=+3/-3 === > y=-3/+3$