Take A and B points and
Let m be the difference of x-coordinates and n, that of y-ones.
[tex]m=|-2-1|=3\;\;\;\;\;n=|4-3|=1[/tex]
With this, we know D is 3 units to the left from C and 1 unit above C, that is:
[tex]D=(4-m,\;-1+n)=(4-3,\;-1+1)=(1,\;0)[/tex]
