Question 190589
{{{c/b-c/(abc)}}} Start with the given expression.



{{{(c*ac)/(b*ac)-c/(abc)}}} Multiply the first fraction by {{{ac/ac}}} to get the denominators equal



{{{(ac^2)/(abc)-c/(abc)}}} Multiply



{{{(ac^2-c)/(abc)}}} Combine the fractions



{{{(c(ac-1))/(abc)}}} Factor out the GCF from the numerator



{{{(cross(c)(ac-1))/(ab*cross(c))}}} Cancel out like terms.



{{{(ac-1)/(ab)}}} Simplify



So {{{c/b-c/(abc)=(ac-1)/(ab)}}} where {{{a<>0}}}, {{{b<>0}}} or {{{c<>0}}}