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## #1 2013-06-29 03:50:35

mukesh
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### locus in co-ordinate geometry

sir plse reply quickly ,i m in very trouble.
'A POINT(6,-8) IS IN XY PLANE.FIND THE LOCUS OF THE MID POINT OF ALL THE POSSIBLE LINES DRAWN FROM THIS POINT WHICH INTERSECT X-AXIS.

## #2 2013-06-29 03:58:28

bobbym

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### Re: locus in co-ordinate geometry

Hi;

I am getting y = - 4.

In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

## #3 2013-06-29 04:01:46

bob bundy
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### Re: locus in co-ordinate geometry

hi mukesh,

Did you try plotting a few points to see what happens?

Let the 'other' end of the line be at (x,0)

The end points are (x,0) and (6,-8)

So what is the y coordinate of the midpoint?

That should fix the locus for you.

Bob

You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

## #4 2013-06-29 11:50:15

{7/3}
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### Re: locus in co-ordinate geometry

Not sure,but won't the locus be a segment of a parabola?

There are 10 kinds of people in the world,people who understand binary and people who don't.

## #5 2013-06-29 12:21:08

bobbym

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### Re: locus in co-ordinate geometry

Hi;

I assumed he meant all the line segments from (6,-8) to the x axis. A few sample points are shown with the red point being the midpoint.

In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

## #6 2013-06-29 16:32:08

{7/3}
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### Re: locus in co-ordinate geometry

Sorry,i mixed up locus and envelope.

There are 10 kinds of people in the world,people who understand binary and people who don't.