[tex]\dfrac{6x-24}{16-x^2}\\\\=\dfrac{6(x-4)}{4^2 -x^2}\\\\=\dfrac{6(x-4)}{(4+x)(4-x)}\\\\=-\dfrac{6(x-4)}{(x+4)(x-4)}\\\\=-\dfrac{6}{x+4}[/tex]
