Question 439689
the first step is to simplify each fraction separately...

first simplify: {{{(x^2-36)/(x^2-8x+16)}}}={{{((x+6)(x-6))/((x+4)(x-4))}}}

then: {{{(3x-18)/(x^2-x-12)}}}={{{3(x-6)/((x-4)(x+3))}}}

then since it is a division between polynomials it becomes a multiplication by finding the reciprocal of the denominator and looks like this:

{{{((x+6)(x-6))/((x+4)(x-4))}}}*{{{((x-4)(x+3))/(3(x-6))}}} and by simplifying common terms on the numerator and the denominator we obtain: {{{((x+6)(x+3))/(3(x-4))}}}