Question

$frac{ m^{2}+9 }{m^{2}-9} - frac{ m+3 }{m-3}=$

Answer 1

(m²+9)/[(m-3)(m+3)]-(m+3)/(m-3)=(m²+9-m²-6m-9)/(m²-9)=
=-6m/(m²-9)=6m/(9-m²)