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Expert replies
by vinay1983 » Wed Oct 09, 2013 3:45 am
Is there any condition for determining whether 2 lines are perpendicular in a co-ordinate plane?Explanation with a example would be great.
You can, for example never foretell what any one man will do, but you can say with precision what an average number will be up to!
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Source: — Problem Solving |

by theCodeToGMAT » Wed Oct 09, 2013 3:54 am
When the Product of slopes of two lines results "-1", the lines are said to be perpendicular.
let LINE 1: Y = MX + C
line 2: y = mx + c

If, M * m = -1--> Perpendicular lines.
R A H U L
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by rakeshd347 » Wed Oct 09, 2013 4:08 am
vinay1983 wrote:Is there any condition for determining whether 2 lines are perpendicular in a co-ordinate plane?Explanation with a example would be great.
When the product of slope of two lines equal to -1 than the two lines are perpendicular to each other.
In other words you can also say that the slope of perpendicular lines are negative reciprocal of each other. If the slope of one line is 3 then the perpendicular line to it will have the slope of -1/3.

whenever you see a line equation in this form 2x+3y=6….first convert it into this for y=mx+c….so y=-2/3x+2….So the line perpendicular to this will have a slope of 3/2.

I hope its clear.

Thanks.
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by vinay1983 » Wed Oct 09, 2013 4:38 am
In other words you can also say that the slope of perpendicular lines are negative reciprocal of each other. If the slope of one line is 3 then the perpendicular line to it will have the slope of -1/3.
Yes!this is what i wanted.
You can, for example never foretell what any one man will do, but you can say with precision what an average number will be up to!
Join the discussion