A dilation with scale factor -3 maps X to X' and Y to Y'. Given X'Y'=2, find XY.
Lets call the point of dilation O.
XX'=4XO
YY'=4YO
XO=1/4 of XX'
YO=1/4 of YY'
X'Y'=4XY
XY=X'Y'/4
X'Y'=2
XY=$\boxed{\dfrac12}$
+591 
