Locus problem help ! (1 Viewer)

aanthnnyyy

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Q. Write down the equation of the locus of a point P that is 2 units from the point A(1,-3)

I assume you have to use distance formula but I'm sorta stuck :/
 

InteGrand

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Q. Write down the equation of the locus of a point P that is 2 units from the point A(1,-3)

I assume you have to use distance formula but I'm sorta stuck :/
Just a circle of radius 2 units, with A as the centre.
 

DatAtarLyfe

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Can you post the question? Cause if it says "always 2 units from A(1,-3)" then the locus is just a circle,
And the equation would be: (x - 1)^2 + (y + 3)^2 = 4
 

aanthnnyyy

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Just a circle of radius 2 units, with A as the centre.
Zz damnit. I remember last time I did a locus question and realized its not always a circle so I felt unsure. Thanks anyways shoulda just stuck to my instincts
 

aanthnnyyy

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Can you post the question? Cause if it says "always 2 units from A(1,-3)" then the locus is just a circle,
And the equation would be: (x - 1)^2 + (y + 3)^2 = 4
that was the exact question but I guess it's a little ambiguous as it doesn't say ALWAYS, but I assume it's a circle since it's only 1 mark so ye
 

braintic

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Can you post the question? Cause if it says "always 2 units from A(1,-3)" then the locus is just a circle,
And the equation would be: (x - 1)^2 + (y + 3)^2 = 4
It doesn't have to say "always".
 

DatAtarLyfe

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It doesn't have to say "always".
I never said it does, but with the limited information i was given i assumed it went always otherwise they would have provided another point or a line to equate the distances.
Is that what you're saying? or are you saying for circle loci they don't need to write "always"?
 

Ambility

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You can intuit it out, but knowing how the formal method works is also important. It uses the distance formula.

 

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