Hi All,
We're asked for a line that is PERPENDICULAR to Line K in the figure above. This question is based on 'line rules' and requires a bit of Arithmetic to solve.
Perpendicular lines have an 'opposite inverse' (re: "negative reciprocal") slope. For example, if one line has a slope of 3, then a perpendicular line to that first line would have a slope of -1/3. As such, we have to find the slope of Line K first - and then we'll know the slope of the perpendicular line that we're looking for.
From the drawing, we can see that Line K hits points (0, -6) and (12, 0), so it has a slope of +6/12 = +1/2. Thus, the perpendicular line that we're looking for has a slope of -2.
The simplest version of that type of line would be Y = -2X. You'll notice that none of the answer choices are written in that format... but if we add "2X" to both sides, we would have an equation that included Y + 2X..... and we do have one answer in that format. Since that equation has no other variables (it's Y + 2X = 12)... that line has a slope of -2, so it must be the answer.
Final Answer: D
GMAT assassins aren't born, they're made,
Rich
