Coordinate Geometry

[stevefeiner5]

Line l is defined by the equation y - 5x = 4 and line w is defined by the equation 10y + 2x + 20 = 0. If line k does not intersect line l, what is the degree measure of the angle formed by line k and line w? (Assume that all lines lie in one coordinate plane.)

0


30


60


90


It cannot be determined from the information given



I understand that to never touch line L one of the options is a line that is parallel to it and thus would be perpendicular to line W, but wouldn't another option that would never touch line L be a parabola? I don't know if the gmat expects us to ignore this, but It just seems like you can draw several other lines that may not have any sort of intersection with line W so it would appear that it can not be determined?

Please help me understand this.

Thanks,

Steve

[tim]

A parabola is NOT a line and a line is NOT a parabola. i trust this answers your question sufficiently; if not, please reply to let us know..

[stevefeiner5]

Yeah that helps thanks. So anytime the GMAT mentions line, it has to be linear?

thanks

Steve

[debmalya.dutta]

the slope of the line l is 5 and the slope of the line w is -5 and hence l is perpendicular to w .

Now it is mentioned that k does not intersect l and so k is parallel to l .

So since l || k and l perpendicular to w ..Hence k perpendicular to w

Answer is 90

[tim]

Steve, that's kind of the definition of a line.. :)

[mukesh.chh]

Hi,

Sorry to open this old post. I am just curious - If the angle between the 2 lines is not 90 (say its 30, 45 or 60), then what can be the relationship of slopes (m1 and m2) of lines w and k?

As far as i know, by looking at the slopes of 2 lines, we can only deduce whether they are parallel, i.e. m1 = m2, or whether they are perpendicular, i.e. m1 = -1/m2.

So in this question, the only possible answers are 0, 90, or cannot be determined?

Can anyone please confirm whether my assumption is correct?

Thanks

[tim]

you won't be asked about this on the GMAT..