Question 147471


{{{(x+3)/(x^2-9)}}} Start with the given expression.



{{{((x+3))/((x-3)*(x+3))}}} Factor {{{x^2-9}}} to get {{{(x-3)*(x+3)}}}.



{{{(highlight(x+3))/((x-3)highlight(x+3))}}} Highlight the common terms. 



{{{(cross(x+3))/((x-3)cross(x+3))}}} Cancel out the common terms. Note: when you divide {{{(x+3)/(x+3)}}}, the result is 1 and not 0.



{{{(1)/((x-3))}}} Simplify. 



So {{{(x+3)/(x^2-9)}}} simplifies to {{{(1)/((x-3))}}}.



In other words, {{{(x+3)/(x^2-9)=(1)/((x-3))}}} where {{{x<>-3}}} or {{{x<>3}}}