The coordinates of the original figure are:
(-2,1)
(3,1)
(1,3)
(-2,3)
A dilation by a negative scale factor produces an image on the other side of the center of enlargement.
As the first dilation is by a factor of -1 centered at the origin, the length of the sides doesn't change, but the new coordinates will be:
[tex](x,y)\to(kx,ky)[/tex]
Apply this to the given coordinates:
[tex]\begin{gathered} (-2,1)\to(-1\cdot-2,-1\cdot1)\to(2,-1) \\ (3,1)\to(-1\cdot3,-1\cdot1)\to(-3,-1) \\ (1,3)\to(-1\cdot1,-1\cdot3)\to(-1,-3) \\ (-2,3)\to(-1\cdot-2,-1\cdot3)\to(2,-3) \end{gathered}[/tex]
The image after the first dilation looks like this:
Now, the second dilation is by a scale factor of 2, centered at (-1,1).
As it is not centered in the origin, we can use the following formula:
[tex](x,y)\to(k(x-a)+a,k(y-b)+b)[/tex]
Where k is the scale factor and (a,b) are the coordinates of the center of dilation.
By applying this formula to the actual coordinates we obtain:
[tex]\begin{gathered} (2,-1)\to(2(2-(-1))+(-1),2(-1-1)+1)\to(5,-3) \\ (-3,-1)\to(2(-3-(-1))+(-1),2(-1-1)+1)\to(-5,-3) \\ (-1,-3)\to(2(-1-(-1))+(-1),2(-3-1)+1)\to(-1,-7) \\ (2,-3)\to(2(2-(-1))+(-1),2(-3-1)+1)\to(5,-7) \end{gathered}[/tex]
If we place these coordinates in the coordinate plane we obtain:
The answer is option B.
