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Dividing an Interval in a Ratio (1 Viewer)

bujolover

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The point P(-3,8) divides the interval AB externally in the ratio k:1. If A is the point (6,-4) and B is the point (0,4), find the value of k.

In this question, I got 3, but the answer says -3. Wouldn't that be incorrect, as our teacher told us that if the question says a point externally divides in a negative ratio, then that effectively cancels out to be an internal division (in the same way that two negatives make a positive)? Clearly P externally divides AB, as the abscissa of P lies outside the range of those between A and B.

Thanks in advance. :)
 

pikachu975

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The point P(-3,8) divides the interval AB externally in the ratio k:1. If A is the point (6,-4) and B is the point (0,4), find the value of k.

In this question, I got 3, but the answer says -3. Wouldn't that be incorrect, as our teacher told us that if the question says a point externally divides in a negative ratio, then that effectively cancels out to be an internal division (in the same way that two negatives make a positive)? Clearly P externally divides AB, as the abscissa of P lies outside the range of those between A and B.

Thanks in advance. :)
It should be 3 if that question was asked in the HSC but usually most people when doing external division they make one of the ratios negative which is why the answers might say that. Do you have a picture of the answers?
 

bujolover

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It should be 3 if that question was asked in the HSC but usually most people when doing external division they make one of the ratios negative which is why the answers might say that. Do you have a picture of the answers?
This was actually a past HSC question (1991 1c), so I guess I was right. There's no point attaching the answers, because it just says -3 for that question, and I already wrote that it said that anyway.

Thanks for the confirmation. :)
 

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