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In a acute angled triangle ABC, proint D...

In a acute angled triangle ABC, proint D, E and F are the feet of the perpendiculars from A,B and C onto BC, AC and AB, respectively. H is orthocentre. If `sinA=3/5a n dB C=39 ,` then find the length of `A H`

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Given `sin A = 3//5`
`rArr cos A = 4//5`
Also `a = 39`
`:. (a)/(sin A) = 2R`
or `(39 xx 5)/(3) = 2R`
or `2R = 65`
`rArr AH = 2R cos A = 65 xx (4)/(5) = 52`
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