Question 149205
{{{7x/(x^2+5x+6)-3/(x+3)}}}


Factor {{{x^2+5x+6}}}


{{{7x/(x+3)(x+2)-3/(x+3)}}}


So the common denominator is (x+3)(x+2).  So multiply the second fraction by x+2/x+2:


{{{7x/(x+3)(x+2)-3(x+2)/(x+3)(x+2)}}}


Subtract the numerators over a common denominator
{{{(7x-3(x+2))/(x+3)(x+2)}}}


Simplify 7x-3(x+2)

{{{(7x-3x-6)/(x+3)(x+2)}}}


Combine like terms
{{{(4x-6)/(x+3)(x+2)}}}