Question 56056
Assuming that your problem looks like this ....
{{{ 6/(x-5) -1/(3x-15) +4/(5-x) }}}
factor out a -1 from the denom of the 3rd fraction
{{{ 6/(x-5) -1/(3x-15) +4/-1(x-5) }}}
factor out a 3 from the denom. of the 2nd fraction
{{{ 6/(x-5) -1/3(x-5) +4/-1(x-5) }}}
Multiply the 1st and 3rd fraction by 3/3
{{{ 6(3)/(3)(x-5) -1/3(x-5) +4(3)/-1(3)(x-5) }}}
find the numerators, remeber that the - in the denominator changes the fraction to a negative
{{{ 18/3(x-5) -1/3(x-5) -12/3(x-5) }}}
combine into one fraction
{{{ (18 -1 -12)/ 3(x-5) }}}
work the numerator
{{{ 3/3(x-5) }}}
reduce
{{{ 1/(x-5) }}}