collection of tough problems from G PREP - 4

[abhasjha]

does line k intersect quad II (upper left hand quadrant)?

1) slope of K = -1/6

2) y-int of k = -6

[harsh.champ]

does line k intersect quad II (upper left hand quadrant)?

1) slope of K = -1/6

2) y-int of k = -6

As I had mentioned before, the slope and the intercept is required to determine the equation of a unique line.
Only knowing 1 of the 2 variables is insufficient.
Hence,the equation becomes,y=(-1/6)x -6

Hence, the answer would be C.

[ajith]

does line k intersect quad II (upper left hand quadrant)?

1) slope of K = -1/6

2) y-int of k = -6

1) slope of K = -1/6

It is not possible for a -ve sloped line not to cross second quadrant [ It may or may not intersect 3rd and 1st quadrant]

Sufficient

2) Insufficient - a positively sloped line can be framed such that it has -ve y intercept and not touch 2nd quadrant at all. similarly a -vely sloped line always passes through second quadrant

A