Решите систему уравнений способом подстановки

5) $\left \{ {{x + 5y = -2} \atop {0.5x - y = 6}} \right. \\ \left \{ {{x + 5y = -2} \atop {0.5x = 6 + y}} \right. \\ \left \{ {{x + 5y = -2} \atop {x = 12 + 2y}} \right. \\ \left \{ {{12 + 2y + 5y = -2} \atop {x = 12 + 2y}} \right. \\ \left \{ {{7y= -14} \atop {x = 12 + 2y}} \right. \\ \left \{ {{y= -2} \atop {x = 12 - 4}} \right. \\ \left \{ {{y= -2} \atop {x = 8}} \right. \\$

6) $\left \{ {{12x - y = 18} \atop {x + 0.5y = 5}} \right. \\ \left \{ {{12x - y = 18} \atop { 0.5y = 5 - x}} \right. \\ \left \{ {{12x - y = 18} \atop { y = 10 - 2x}} \right. \\ \left \{ {{12x - 10 + 2x = 18} \atop { y = 10 - 2x}} \right. \\ \left \{ {{14x = 28} \atop { y = 10 - 2x}} \right. \\ \left \{ {{x = 2} \atop { y = 10 - 2x}} \right. \\ \left \{ {{x = 2} \atop { y = 10 - 4}} \right. \\ \left \{ {{x = 2} \atop { y = 6}} \right. \\$
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