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LOCUS question types - just a quick question (1 Viewer)

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Hey, our class just started on LOCUS last lesson, and our teacher gave us the homework: write 3 of our own REAL DISTANCE questions, and 3 LOCUS questions and do them in our book.

Now, i wasnt completely sure what he meant. We didnt do much in class on the topic yet, it was only one lesson so far.

For the 3 locus questions i wrote some variations of "3 units from the point (2,-3)" and drew the circle and the formula for it (i.e. [ (x-2)^2 + (y+3)^2 = 3 ] ). I was pretty sure what he meant for the locus type questions...

For the real distance i didnt know, i guessed and wrote "3 units to the right of the y axis" and drew it... but...? I don't know what else to do - they were the only things we did in class...? help greatly appreciated!
 

rama_v

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Um Im not quite sure, maybe he means a question like this:
"By using the perpendicular distance formula, find the locus of a point P(x,y) which is equidistant from the lines 3x + 4y =36 and 4x + 3y=24"??
 

Trev

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psycho_orange01 said:
For the 3 locus questions i wrote some variations of "3 units from the point (2,-3)" and drew the circle and the formula for it (i.e. [ (x-2)^2 + (y+3)^2 = 3 ] ). I was pretty sure what he meant for the locus type questions...
That would be incorrect anyway.
'Three units from the point (2,-3)", you should state the point as being the centre of circle, and radius of 3. But remember the equation of circle is as follows:
(x-h)<sup>2</sup>+(y-k)<sup>2</sup>=r<sup>2</sup>
Where centre circle (h,k) and radius is 'r'.
So the equation you wrote would be (x-2)<sup>2</sup>+(y+3)<sup>2</sup>=3<sup>2</sup>
(x-2)<sup>2</sup>+(y+3)<sup>2</sup>=9 (note: it is 9, not 3)
 

KFunk

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Find the locus of the point P(x,y) that is equidistant from the line y=-1 and the point (0, 1)
 

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