Question 883684
{{{drawing(300,300,-5,9,-7,7,grid(1),
circle(4,5,0.3),
circle(7,0,0.3),
circle(1,-4,0.3))}}}
To go from G to F, you move 6 units in x and 4 units in y. 
So to go from E to H, move -6 units in x and -4 units in y.
(4,5)+(-6,-4)=(-2,1)
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{{{drawing(300,300,-5,9,-7,7,grid(1),
circle(4,5,0.3),
circle(7,0,0.3),
circle(1,-4,0.3),
circle(-2,1,0.3),
blue(line(1,-4,7,0)),
blue(line(7,0,4,5)),
blue(line(4,5,-2,1)),
blue(line(-2,1,1,-4)))}}}
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H=(-2,1)