Question 195793
Factor the numerator and the denominator, then cancel like values

{{{(x^2-x-6)/(x^2-4)}}}
{{{((x-3)(x+2)) / ((x-2)(x+2))}}}
{{{(x-3)/(x-2)}}}

For a nice tool to help you factor, use this --> http://72.3.253.76:8080/webMathematica3/quickmath/page.jsp?s1=algebra&s2=factor&s3=basic