Answer:
(x,y) → (ax,ay) .
Explanation:
A dilation is a transformation that changes the size of the image. It either shrink or enlarge a shape by using a scale factor about a center of dilation.
If we transform point (x,y) by using dilation with scale factor k (assume center of dilation at (0,0) then the coordinate of the image will be (kx,ky).
So, the coordinate expression represents the coordinates of any point after dilation by a scale factor of a:
(x,y) → (ax,ay) .