Question 992121
{{{(x-8)/(x-4)+(x-5)/(x-7)-2}}}


Simplest common denominator is  (x-4)(x-7) so that is the kind of terms you want.


{{{((x-8)/(x-4))((x-7)/(x-7))+((x-5)/(x-7))((x-4)/(x-4))-2(((x-4)(x-7))/((x-4)(x-7)))}}}


{{{((x-8)(x-7)+(x-5)(x-4)-2(x-4)(x-7))/((x-4)(x-7))}}}


{{{(x^2-15x+56+x^2-9x+20-2(x^2-11x+28))/((x-4)(x-7))}}}


{{{(2x^2-24x+75-2x^2+44x-56)/((x-4)(x-7))}}}


{{{(20x+75-56)/((x-4)(x-7))}}}


{{{highlight((20x+19)/(x^2-11x+28))}}}