Given: P(α,β,γ) be the foot of the perpendicular from the point Q(1,2,3) on the line 5x+3=2y−1=3z+4
Now, let 5x+3=2y−1=3z+4=λ
So, any point on the line is given by (5λ−3,2λ+1,3λ−4), so let the point be P(5λ−3,2λ+1,3λ−4)
Now, direction ratio of PQ=(5λ−4,2λ−1,3λ−7)
Now, the line and PQ will be perpendicular,
So, 5(5λ−4)+2(2λ−1)+3(3λ−7)=0
⇒38λ−43=0
⇒λ=3843
So, the point P(α,β,γ)=P(5×3843−3,2×3843+1,3×3843−4)
Then 19(α+β+γ)=19[5×3843−3+2×3843+1+3×3843−4]
⇒19(α+β+γ)=19[38101+124−23]
⇒19(α+β+γ)=101