Hi sana.noor,
For this DS question, you can probably get through the first couple of steps fairly quickly, but you'll need a drawing to get through the final step.
We're told that there are 3 points: A, B and C. We're asked if the slope of line BC is negative. This is a YES/NO question.
Fact 1 tells us that line AB has a -1 slope. This doesn't tell us anything about where point C is relative to the other points.
So, the slope of BC could be positive and the answer is NO.
The slope of BC could be negative and the answer is YES.
Inconsistent = INSUFFICIENT
Fact 2 tells us that angle ABC is 37 degrees. We still don't know the slopes of anything.
Inconsistent = INSUFFICIENT
Combining steps, you'll want to draw a picture...
Line AB has a slope of -1. Draw THAT LINE. With a -1 slope, you'll be going down-and-to-the-right at a 45 degree angle.
Line BC has to come off of that first line at a 37 degree angle. If you draw all the possibilities, you'll see that line BC will ALWAYS be negative.
Consistent YES answer = SUFFICIENT
GMAT assassins aren't born, they're made,
Rich
