Ответ:

  1. \(\dfrac{6a+6b}{9a}=\dfrac{3(a+b)}{9a}=\dfrac{a+b}{3a}\).
  2. \(\dfrac{8y}{4x-4y}=\dfrac{8y}{4(x-y)}=\dfrac{2y}{x-y}\).
  3. \(\dfrac{ab-ad}{abd}=\dfrac{a(b-d)}{abd}=\dfrac{b-d}{bd}\).
  4. \(\dfrac{xyz}{xz-yz}=\dfrac{xyz}{z(x-y)}=\dfrac{xy}{x-y}\).
  5. \(\dfrac{ax-ay}{ax+ay}=\dfrac{a(x-y)}{a(x+y)}=\dfrac{x-y}{x+y}\).
  6. \(\dfrac{3cd+3d}{6cd-2d}=\dfrac{3d(c+1)}{2d(3c-1)}=\dfrac{3(c+1)}{2(3c-1)}\).
  7. \(\dfrac{2xy+2x}{2x+2xz}=\dfrac{2x(y+1)}{2x(1+z)}=\dfrac{y+1}{z+1}\).
  8. \(\dfrac{ad+acd}{abd-acd}=\dfrac{ad(1+c)}{ad(b-c)}=\dfrac{c+1}{b-c}\).