Question

Помогите пожалуйста, даю 50 баллов

Answer 1

$\left \{\begin{array}{l}6x-18y-12=0} \\ {6x-9y+6=0}}\end{array} \right.\\\\\\-\left \{\begin{array}{l}6x-18y-12=0} \\ {6x-9y+6=0}}\end{array} \right. \\-----------\\0x+9y+18=0$