Question

Решить систему уравнений

Answer 1

$frac{x + 7}{3} - frac{y - 8}{5} = 3 \ frac{x + 5}{4} + frac{y + 9}{3} = 5 \ \ 5(x + 7) - 3(y - 8) = 45 \ 3(x + 5) + 4(y + 9) = 60 \ \ 5x + 35 - 3y + 24 = 45 \ 3x + 15 + 4y + 36 = 60 \ \ 5x - 3y = - 14 \ 3x + 4y = 9 \ \ 20x - 12y = - 56 \ 9x + 12y =27 \ \ 29x = - 29 \ y = frac{9 - 3x}{4} \ \ x = - 1 \ y = frac{9 - 3x}{4} \ \ x = - 1 \ y = frac{9 - 3times ( - 1)}{4} = frac{12}{4} = 3$
ответ: (-1; 3)