Помогите пожалуйста. . . .

Решите задачу:

$\left \{ {{4x-y=-7} \atop {x+3y=-5}} \right. \left \{ {{y=7+4x} \atop {x+3(7+4x)=-5}} \right. \left \{ {{y=7+4x} \atop {x+21+12x=-5}} \right. \left \{ {{y=7+4x} \atop {13x=-26}} \right. \left \{ {{y=7+4(-2)} \atop {x=-2}} \right. \\ \left \{ {{y=-1} \atop {x=-2}} \right. \\......................... \\\left \{ {{6y+3x=5} \atop {5x+3y=-1}} \right. \left \{ {{3x+6y=5} \atop {-10x-6y=2}} \right. \\-7x=7\\x=-1\\6y-3=5\\6y=8\\y= \frac{4}{3}$