I think it's the last point. (5,4)
The answer would be -2 i had the same problem on my quiz and the correct answer was -2
The correct answer is D. D'(1, 5), E'(-1, 3), F'(-1, -4), G'(1, -2).
It's because of this: You need to calculate the distances, and they are in this case symmetric, so you look how far is from one side, and it will be the same on the other side. When you put it on graph, the coordinates are clear and the correct answer is D.
2x^3y+18xy-10x^2y-90y
= 2xy(x^2 + 9)- 10y(x^2 + 9)
= (x^2 + 9)(2xy - 10y)
= (x^2 + 9) 2y(x - 5)
= 2y (x^2 + 9) (x - 5)
