ĐKXĐ: $x \neq -1$ , $y \neq -4$
Đặt $a = \frac{x}{x+1}$ , $b = \frac{1}{y+4}$ ( $b \ neq 0$)
HPT trở thành:$\left \{ {{3a -2b=4} \atop {2a - 5b=9}} \right.$
$⇔ \left \{ {{a=\frac{2}{11}} \atop {b=-\frac{19}{11}}} \right.$
Ta có: $a = \frac{2}{11}$
$⇔ \frac{x}{x+1} = \frac{2}{11}$
$⇔ 11x = 2(x + 1)$
$⇔ 11x = 2x + 2$
$⇔ 9x = 2$
$⇔ x = \frac{2}{9}$ (TM)
Ta có: $b=-\frac{19}{11}$
$⇔ \frac{1}{y+4} = -\frac{19}{11}$
$⇔ y + 4 = -\frac{11}{19}$
$⇔ y = -\frac{87}{19}$ (TM)
Vậy $ x = \frac{2}{9}$ , $ y = -\frac{87}{19}$
