Question

Решить систему линейных уравнений алгебраичнеским способом сложения 7x+3y=10
8x-6y=18

Answer 1

$\left \{ {{7x+3y=10|*2} \atop {8x-6y=18}} \right. \\+\left \{ {{14x+6y=20} \atop {8x-6y=18}} \right. \\22x=38\\x=\frac{19}{11} \\\\\left \{ {{6y=20-14x} \atop {x=\frac{19}{11}}} \right. \\\left \{ {{6y=20-14*\frac{19}{11}} \atop {x=\frac{19}{11}}} \right. \\\left \{ {{y=-\frac{23}{33} }} \atop {x=\frac{19}{11}}} \right. \\(1\frac{8}{11};-\frac{23}{33})$