Start from the parent function 
In the first case, you are computing

In the second case, you are computing
, you translate the function horizontally,
units left if
and
units right if
.
On the other hand, when you transform
, you translate the function vertically,
units up if
and
units down if
.
So, the first function is the "original" parabola
, translated
units right and
units up. Likewise, the second function is the "original" parabola
, translated
units left and
units down.
So, the transformation from
to
is: go
units to the left and
units down