Answer is E.
Both together are not sufficient.
(-a,b) and (-b,a) are in the same quadrant when a and b are both positive or negative. So they can be either 2nd or 4th quadrant.
xy > 0 ==> either x and y are both positive or both negative.
if positive it will be in 2nd Quadrant if negative it will be in 4th Quadrant. Not sufficient.
ax>0 ==> if a is positive x has to be positive. if a is negative x has to be negative. Not sufficient.
Both together
If a is positive x has to be positive, y has to be positive . 2nd Quadrant
if a is negative x has to be negative, y has to be negative 4th quadrant
Answer is E
Thanks
Raama
Coordinate Geometry
This topic has expert replies
Source: Beat The GMAT — Data Sufficiency |
I say the answer is C....
Statement one says XY>0
Which means both ar epositive or both are negative
Statement 2 says AX > 0
Which means X is positive or negative pending what X is equal to.
Now lets go back to the stem....
given the information if both a and are positive then (-a,b) and (-b,a) are in Q2....if both are negative then they are both in Q4
Now lets go back to statement 2....If A is negative then X is negative....and then adding that information to statement one we know Y is also negative....telling us which Quadrant (-X,Y) is located in...which will be in the SAME quadrant as (-a,b) and (-b,a)
Now if A is positive then both (-a,b) and (-b,a) are in Quadrant 2....if A is positive then X is positive meaning Y is positive which means (-x,y) is in the same Quadrant as (-a,b) and (-b,a).....Sooo this is my reasoning behind the C...
Whats the OA?
Statement one says XY>0
Which means both ar epositive or both are negative
Statement 2 says AX > 0
Which means X is positive or negative pending what X is equal to.
Now lets go back to the stem....
given the information if both a and are positive then (-a,b) and (-b,a) are in Q2....if both are negative then they are both in Q4
Now lets go back to statement 2....If A is negative then X is negative....and then adding that information to statement one we know Y is also negative....telling us which Quadrant (-X,Y) is located in...which will be in the SAME quadrant as (-a,b) and (-b,a)
Now if A is positive then both (-a,b) and (-b,a) are in Quadrant 2....if A is positive then X is positive meaning Y is positive which means (-x,y) is in the same Quadrant as (-a,b) and (-b,a).....Sooo this is my reasoning behind the C...
Whats the OA?
You got the same thing I got, but it is asking if the point is in the same Quadrant as a and b....and if you make A positive then it is in 2nd Quadrant, not just point (-x,y) but also (-a,b) and (-b,a) are in 2nd Q.krisraam wrote:Answer is E.
Both together are not sufficient.
(-a,b) and (-b,a) are in the same quadrant when a and b are both positive or negative. So they can be either 2nd or 4th quadrant.
xy > 0 ==> either x and y are both positive or both negative.
if positive it will be in 2nd Quadrant if negative it will be in 4th Quadrant. Not sufficient.
ax>0 ==> if a is positive x has to be positive. if a is negative x has to be negative. Not sufficient.
Both together
If a is positive x has to be positive, y has to be positive . 2nd Quadrant
if a is negative x has to be negative, y has to be negative 4th quadrant
Answer is E
Thanks
Raama
same goes for if a is Negative....its in the 4th Q, but all three points are in the same Quadrant. which is Q 4
