Answer:
[tex]r = \frac{-4}{9}[/tex]
Step-by-step explanation:
[tex]\frac{12r}{r+2}= \frac{4}{r+2} -6 \\\\\frac{12r}{r+2}= \frac{4-6(r+2)}{r+2} \\\\\frac{12r}{r+2}= \frac{4-6r-12}{r+2}\\\\12r = -6r - 8\\\\12r + 6r = -8 \\\\18r = -8\\\\r = \frac{-8}{18} = \frac{-4}{9}[/tex]