If I have a triangle lets say, $\triangle ABC$ and the graph says to apply the dilation $D$ to the polygon with the vertices:
$D: (x, y) \longrightarrow (-2x, -2y)$
$A(2,1), B(2,3), C(5,1)$
Here...
$k < 0$
The shape is then rotated by 180 degrees, and the dilation happens. But...
Is it really a dilation if $k<0$?