We know that in the dominator, the x can't be -6 or -4 because the dominator mustn't be zero. And -6 and -4 makes discontinuities of the function.
Further more, we could CANCEL OUT (x+4) from both numerator and dominator.
And this makes (x+4) REMOVABLE, so that the -4 become a Removable discontinuity.
Now what’s left here is this fraction: