Dilation is enlarging or shrinking of a point on a coordinate plane, polygon or line segment using a specific scale factor.
(x,y) -> (a*x, a*y)
For the given points and a scale factor of 3:
[tex](-4,2)\rightarrow(-4\cdot3,2\cdot3)=(-12,6)[/tex][tex](1,\text{ -3)}\rightarrow(1\cdot3,\text{ -3}\cdot3)=(3,\text{ -9)}[/tex][tex](2,-5)\rightarrow(2\cdot3,-5\cdot3)=(6,-15)[/tex][tex](-1,7)\rightarrow(-1\cdot3,7\cdot3)=(-3,\text{ 21)}[/tex]