GMAT Prep Coordinate Geometry
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Hi,
I believe that the answer is E (because the angle between the two lines cant be decided based upon given information.)
Note that if line K passes through (1, 1) & (1, -1) then it will always pass through (1,0)
Hence both points 1 & 2 are the same piece of information, These elaborate information about line K only.
However no information is provided about line M & its angle with line K
1. All we know about line M is that it passes through (1, -1) which is intersection point, & the angle of intersection cant be decided.
NOT SUFFICIENT
2: this information is again the same as 1 only except that it provides K's intersection point with X axis.
NOT SUFFICIENT
Even after combining 1 & 2, we do not get any additional information. Hence E.
Let me know if I missed anything.
I believe that the answer is E (because the angle between the two lines cant be decided based upon given information.)
Note that if line K passes through (1, 1) & (1, -1) then it will always pass through (1,0)
Hence both points 1 & 2 are the same piece of information, These elaborate information about line K only.
However no information is provided about line M & its angle with line K
1. All we know about line M is that it passes through (1, -1) which is intersection point, & the angle of intersection cant be decided.
NOT SUFFICIENT
2: this information is again the same as 1 only except that it provides K's intersection point with X axis.
NOT SUFFICIENT
Even after combining 1 & 2, we do not get any additional information. Hence E.
Let me know if I missed anything.
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if a line passes through (1,1) and (1,-1) it's equation is x=1, therefore it should pass through (1,x).
draw this and you see why.
if you want a math explanation,
y = mx+b
m=(y2-y1)/(x2-x1) in this case infinite (x2-x1 = 0).
this a case of a vertical line, where x always takes the same value, from the two points you see that the value is one, therefore the equation is x=1 (x is one for all values of y).
if m was 0 the line would be horizontal and you would get y=a line equation (a the value of y for any value of x)
draw this and you see why.
if you want a math explanation,
y = mx+b
m=(y2-y1)/(x2-x1) in this case infinite (x2-x1 = 0).
this a case of a vertical line, where x always takes the same value, from the two points you see that the value is one, therefore the equation is x=1 (x is one for all values of y).
if m was 0 the line would be horizontal and you would get y=a line equation (a the value of y for any value of x)
Thanks Agps,
Just to add, in case of any lines, try to draw a rough sketch of the the points. It will show where the lines might intersect.
For a line you need to know only 2 pieces of information:
1. Any two points through which the line passes.
2. one point through which the line passes + one angle with some other known line.
I believe this will help in future questions.
Let me know if more details are needed.
Thanks,
Bharat.
Just to add, in case of any lines, try to draw a rough sketch of the the points. It will show where the lines might intersect.
For a line you need to know only 2 pieces of information:
1. Any two points through which the line passes.
2. one point through which the line passes + one angle with some other known line.
I believe this will help in future questions.
Let me know if more details are needed.
Thanks,
Bharat.