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Baskaranselva
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 Posted: Mon Aug 18, 2008 10:31 am Post subject: Slope of Line |
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Can someone let me know, how to resolve this question ?
Thanks in advance.
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sudhir3127
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| Posted: Mon Aug 18, 2008 12:01 pm Post subject: Re: Slope of Line |
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| Baskaranselva wrote: | Can someone let me know, how to resolve this question ?
Thanks in advance. |
the very simple logic here is to understand that we know the slope is negative . and for an equation ax + by + c=0 the slope is -a/b
hence it cant be zero and a negative number will make the slope positive..
hence choose a positive value.. which is 6.
hope it helps..
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parallel_chase
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| Posted: Mon Aug 18, 2008 12:16 pm Post subject: |
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I think Sudhir posted the correct solution for the wrong question. The above solution is for the other slope question you posted.
Statement I and II alone are insufficient, because we need both the intercepts to find the slope since no other information is given.
Slope of the line = -a/b
a is the x intercept
b is the y intercept.
slope = -2/3
Hence C is the answer.
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bha
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| Posted: Mon Aug 18, 2008 12:45 pm Post subject: |
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| parallel_chase wrote: | I think Sudhir posted the correct solution for the wrong question. The above solution is for the other slope question you posted.
Statement I and II alone are insufficient, because we need both the intercepts to find the slope since no other information is given.
Slope of the line = -a/b
a is the x intercept
b is the y intercept.
slope = -2/3
Hence C is the answer. |
Shouldn't the slope be -3/2...y-intercept/x-intercept...
slope = (y2-y1)/(x2-x1)= (3-0)/(0-2)= -3/2...
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California4jx
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| Posted: Mon Aug 18, 2008 12:58 pm Post subject: |
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By just knowing an x-intercept - a line could be parallel to y-axis or it can make some slope (in that case you need to know y-intercept) - so I is insufficient
Similarly, just knowing y-intercept could mean a line could be parallel to x-axis or may be making a slop for which you need to know x-intercept
thus, statement II is insuffient
Therefore, by combining statement I and II - you get both x and y intercept to know where the line is heading - and there can find the slope
m = y2 - y1/x2-x1
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rishi235
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| Posted: Mon Aug 18, 2008 10:06 pm Post subject: @ parallel_chase & bha |
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Hi...
I also agree with bha...the slope shud b -3/2...
But now that ax+by+c=0,
y = -a/bx - c/b
Comparing with y=mx+c
m=-a/b = -2/3
This is incorrect as here a & b are co-efficients of x & y and in the problem, we r given the x & y intercepts...
So, slope = - (Y int) / (X int)
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