In the xy-plane, line k passes through the point (1,1) and

Question

In the xy-plane, line k passes through the point (1,1) and line m passes through the point (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).

The OA is E.
Why not A? Could you please explain in detail?

eschn3am · Answer

Sketch out a little diagram.

We have line K passing through point (1,1)
We have line M passing through point (1,-1) which is just 2 spots down in a straight line

1. Line K amd M intersect at point (1,-1) which means line K is a vertical line where X = 1. For M to be perpendicular we need it to be a horizontal line, but this tells us nothing about M. INSUFFICIENT
2. Line K intersects the X-axis at the point (1,0). This is telling us that line K is a vertical line where X = 1, which is something we already figured out from statement 1. Again, line M could be a horizontal line or any other line that passes through (1,-1). INSUFFICIENT

Answer E

maratikus · Answer

charting those two lines is the way to go!

pmenon · Answer

you'll see from the info in stem and stat 1 that k is a vertical line. thats fine, but we need to know whether m is a horizontal line.

Neither stat1 or 2 tell us anything about line m, except one point on it. a line passing through that point COULD be horizontal, but it doesnt HAVE to be.

E

neeraj.kaushal · Answer

As discussed above both statements insufficient and both taken together also tell us about three points for k making it vertical but nothing about m. 
So answer is E

In the xy-plane, line k passes through the point (1,1) and

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