From the question we know that (-a,b) and (-b,a) are in the same quadrant.
Both a and b must have the same sign to be in the same quadrant.
If a=1 and b=1 they would be in quadrant II
If a=-1 and b=-1 they would be in quadrant IV
(1) xy>0
From 1 we know that x and y have the same sign. This doesn't provide enough information to solve.
Insuff
(2) ax>0
From 2 we know that a and x have the same sign. Also, b will have the same sign because we know a and b have the same sign. However, we don't know if y has the same sign.
Insuff
Together we know that a, b, x, and y all have the same sign. Therefore, (-x,y) will be in the same quadrant as (-a,b) and (-b,a).
If they are all positives they will be in quadrant II. If they are all negatives they will be in quadrant IV.
I choose C.
Logitech DS Set 1
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logitech
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@dmateer25
Great grasp of the knowledge!From the question we know that (-a,b) and (-b,a) are in the same quadrant.
Both a and b must have the same sign to be in the same quadrant.
If a=1 and b=1 they would be in quadrant II
If a=-1 and b=-1 they would be in quadrant IV
Great ending!Together we know that a, b, x, and y all have the same sign. Therefore, (-x,y) will be in the same quadrant as (-a,b) and (-b,a).
If they are all positives they will be in quadrant II. If they are all negatives they will be in quadrant IV.
And the OA is CI choose C.
LGTCH
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