Question 201978
{{{((a-b)^2)/(a^2-b^2)}}} Start with the given expression.



{{{((a-b)(a-b))/(a^2-b^2)}}} Expand the numerator



{{{((a-b)(a-b))/((a-b)(a+b))}}} Factor the denominator



{{{(highlight((a-b))(a-b))/(highlight((a-b))(a+b))}}} Highlight the common terms.



{{{(cross((a-b))(a-b))/(cross((a-b))(a+b))}}} Cancel out the common terms.



{{{(a-b)/(a+b)}}} Simplify



So {{{((a-b)^2)/(a^2-b^2)=(a-b)/(a+b)}}}