[tex]1) \frac{x^2-3x}{x^2+7x-30} = \frac{5x^2-x-42}{x^2+7x-30}

2) x^2+ \frac{3x-1}{x+4}=16- \frac{1-3x}{x+4}

3) \frac{1}{3x+2}+ \frac{3}{5x+6}= \frac{2}{7x+8}[/tex]

4)[tex] \frac{12}{x^2-9} + \frac{x}{x+3}= \frac{2}{x-3} [/tex]