Question

Допоможіть будь-ласка 7-клас

Answer 1

$\displaystyle\bf\\\left \{ {{5x - 6y = 4} \atop { - \frac{x + 3y}{2} = 3 + \frac{x - 7y + 1}{5} \: \: | \times 10}} \right. \\ \displaystyle\bf\\\left \{ {{5x - 6y = 4} \atop { - 5(x + 3y) = 30 + 2(x - 7y + 1) }} \right. \\ \displaystyle\bf\\\left \{ {{5x - 6y = 4} \atop { - 5x - 15y = 30 + 2x - 14y + 2 }} \right. \\ \displaystyle\bf\\\left \{ {{5x - 6y = 4} \atop { - 7x - y = 32 \: \: | \times ( - 6) }} \right. \\ \displaystyle\bf\\ + \left \{ {{5x - 6y = 4} \atop {42x + 6y = - 192 }} \right. \\ \\ 5x + 42x = - 192 + 4\\ 47x = - 188 \\ x = - 188 \div 47 \\ x = - 4 \\ \\ 5 \times ( - 4) - 6y = 4 \\ - 20 - 6y = 4 \\ 6y = - 20 - 4 \\ 6y = - 24 \\ y = - 24 \div 6 \\ y = - 4$

Ответ: ( - 4 ; - 4 )