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Question
If `bara, barb, barc` are position vectors of the points A, B, C respectively such that `3bara+ 5barb-8barc = 0`, find the ratio in which A divides BC.
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Solution
Given : `3bara+ 5barb-8barc = 0`
`3bara=8barc- 5barb `
`bara=(8barc- 5barb)/3 `
`bara=(8barc- 5barb)/(8-5) ` `[∵3=8-5]`
`A(bara)` divides BC externally in the ratio 8 : 5.
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