Bagaimana cara menyederhanakan bentuk aljabar [tex] \frac{4}{x+3} [/tex] - [tex] \frac{5}{x-1} [/tex]

[tex] \frac{4}{x+3} - \frac{5}{x-1} = \frac{(4(x-1)-5(x+3)}{(x+3)(x-1)} \\ \\ \frac{4}{x+3} - \frac{5}{x-1} = \frac{(4x-4)-(5x+15)}{x^2+2x-3} \\ \\ \frac{4}{x+3} - \frac{5}{x-1} = \frac{-x-19}{ x^{2} +2x-3} [/tex]