Question 175208
Factor both numerator and denominator.
{{{10x^2-30x+20=10(x^2-3x+2)=10(x-2)(x-1)}}}
{{{x^2-1=(x+1)(x-1)}}}
{{{(10x^2-30x+20)/(x^2-1)=(10(x-2)(x-1))/((x+1)(x-1))}}}
{{{(10x^2-30x+20)/(x^2-1)=(10(x-2)cross((x-1)))/((x+1)cross((x-1)))}}}
{{{(10x^2-30x+20)/(x^2-1)=(10(x-2))/(x+1)}}}