What is the 4th coordinate for the given coordinates (-1,2),(3,6), and (-2,4) to become a parallelogram?

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1 Answer

H(0,0) and G(5,2)

Explanation:

Given intersection of the diagonals D(1,2)=D(xD,yD)
All that is needed is to solve for the endpoints of the diagonals.
The formula

xD=xE+xG2

1=3+xG2

2=3+xG

xG=5

Also

yD=yE+yG2

2=6+yG2

4=6+yG

yG=2

and therefore G(5,2)

For the other point H(xH,yH)

xD=xF+xH2

1=2+xH2

2=2+xH

xH=0

Also

yD=yF+yH2

2=4+yH2

4=4+yH

yH=0

and therefore H(0,0)

God bless.....I hope the explanation is useful.