GMAT PREP

[trangle]

In the xy-plane, line k passes through the point (1,1) and line m passes through (1,-1). Are line k and m perpendicular to each other?
1. Line k and m intersect at the point (1,-1)
2. Line k intersects the x-axis at the point (1,0)

OA: E

[anshumishra]

In the xy-plane, line k passes through the point (1,1) and line m passes through (1,-1). Are line k and m perpendicular to each other?
1. Line k and m intersect at the point (1,-1)
2. Line k intersects the x-axis at the point (1,0)

OA: E

Try to draw these lines on a co-ordinate plane.

1 and 2, both suggest that line "k" is perpendicular to x-axis and meets at (1,0) BUT, there is no information about the line "m".
Hence one can draw a line passing through (1,-1) and perpendicular to the line "k" or any other line with some other slope --
Clearly Insufficient -- E