Question 119844
(((2x-6)/21)/((5x-15)/12)  multiply both the numerator and denominator by 12/(5x-15).  This will make the denominator equal to 1 and thus get rid of the complex fraction.
((2x-6)/21)(12/(5x-15))/((5x-15)/12)(12/(5x-15)) and this equals

(12(2x-6))/(21(5x-15))/1 and this equals

24(x-3)/105(x-3)=24/105=8/35  check my work


Hope this helps---ptaylor