The coordinates of the foot of the perpendicular drawn from the origin to the line joining the points (-9,4,5) and (10, 0, -1) will be

Let AD be the perpendicular and D be the foot of the perpendicular which divides .BC in the ratio λ:1, then D10λ−9λ+1,4λ+1,−λ+5λ+1The direction ratios of AD, 10λ−9λ+1,4λ+1 and −λ+5λ+1and direction ratios of BC are 19, - 4 and  -6.  Since AD⊥BC, we get 1910λ−9λ+1−44λ+1−6−λ+5λ+1=0or   λ=3128Hence, on putting the value of λ in (i), we get required foot of the perpendicular, i.e.,5859,11259,10959