(x/х^2-8x+16 - x+6/х^2-16): х+12/х^2-16 выражение

(х/(х-4)²-(х+6)/(х-4)(х+4))÷(х+12)/(х+4)(х-4)
((х*(х+4)-(х+6)*(х-4))/(х-4)²(х+4))÷(х+12)/(х+4)(х-4)
(2х+24)/(х-4)²(х+4)×(х+4)(х-4)/(х+12)
2(х+12)/(х-4)*1/(х+12)
2/(х-4)