Question 869040
The addition of the two rational expressions requires changing each rational expression into an equivalent one using the simplest common denominator (like Lowest Common Denominator.)


{{{x^2+x-6=(x-2)(x+3)}}} and {{{x^2-4x+4=(x-2)(x-2)}}}.
These as denominators mean that the "lowest" common denominator is {{{(x-2)(x-2)(x+3)}}}.


The first summand, 
{{{10/(x^2+x-6)=((10)/(x^2+x-6))((x-2)/(x-2))=(10(x-2))/((x-2)(x+3)(x-2))}}};


and you will use a different factor of 1 for the second summand.