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jnney

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Find the ratio if the point C(-9,7) divides the interval A(1,32) and B(-5,17) externally.

Let the ratio be m:n

-9= (1)(n)-(-5)(m)/n-m and 7=(32)(n)-(17)(m)/n-m

-10n-4m=0 and -25n+10m=0


...??????
 

Aysce

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Try simultaneous equations? And doing maths at this time :L. True dedication.
 

Drongoski

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Find the ratio if the point C(-9,7) divides the interval A(1,32) and B(-5,17) externally.

Let the ratio be m:n

-9= (1)(n)-(-5)(m)/n-m and 7=(32)(n)-(17)(m)/n-m

-10n-4m=0 and -25n+10m=0


...??????

You were almost there. Your 1st eqn should have ended up: 4m = 10n and not 4m = -10n.

Then straightaway: m:n = 5:2

Note you need solve only 1 eqn; you don't need to find m & n individually - you only need to find their relative value; i.e their ratio.






Edit

Didn't I urge you all not to stay up too late.
 
Last edited:

Aysce

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Guess my suggestion was a little bit too far off >.<
 

SpiralFlex

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Most people school students dont really lurk the other sections of this forum, pretty sure most people would've missed it.
I live here in the Preliminary forum. It's Spiral's secret hide-out.
 

jnney

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You were almost there. Your 1st eqn should have ended up: 4m = 10n and not 4m = -10n.

Then straightaway: m:n = 5:2

Note you need solve only 1 eqn; you don't need to find m & n - you only need to find their relative value; i.e their ratio.






Edit

Didn't I urge you all not to stay up too late.
Thanks :D
 

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