2x^2-8x-42 over 6x^2 divided by x^2-9 over x^2-3x

Answer 1

2x^2-8x-42 over 6x^2 divided by x^2-9 over x^2-3x
= (2x^2-8x-42)/(6x^2) ÷ [(x^2-9)/(x^2-3x)]
= 2(x+3)(x-7/(6x^2)*x(x-3)/[(x+3)(x-3)]
= (x-7)/(3x) after some lovely canceling.

Answer 2

(x-3)(x^2+x-7)