Помогите решить систему лилейных уравнений
3х+10у=-12
8х+4у=-7

$left { {{3x+10y=-12} atop {8x+4y=-7}} right.$

$left { {{3x+10y=-12} atop {-20x-10y=17.5}} right.$

$left { {{-17x=5.5} atop {3x+10y=-12}} right.$

$left { {{x=5.5:(-17)} atop {10y=-12-3x}} right.$

$left { {{x= frac{55}{10} :(-17)} atop {10y=-12-3x}} right.$

$left { {{x= frac{11}{2} *(- frac{1}{17}) } atop {10y=-12-3x}} right.$

$left { {{x=- frac{11}{34} } atop {10y=-12-3*(- frac{11}{34})$

$left { {{x=- frac{11}{34} } atop {10y=-12+ frac{33}{34}$

$left { {{x=- frac{11}{34} } atop {10y=-11 frac{1}{34}$

$left { {{x=- frac{11}{34} } atop {y=- frac{375}{34}* frac{1}{10}$

$left { {{x=- frac{11}{34} } atop {y=- frac{375}{340}$

$left { {{x=- frac{11}{34} } atop {y=- 1 frac{7}{68}$

Ответ: $(- frac{11}{34} ;-1 frac{7}{68})$