Let,
L1=2x−1=3y−2=αz−3=λ
L2=5x−4=2y−1=βz−0=μ
For point of intersection
2λ+1=5μ+4...(i)
3λ+2=2μ+1...(ii)
αλ+3=βμ+0...(iii)
From (i) and (ii), we get λ=μ=−1
Now, from (iii), we get α−β=3
Let y=8αβ
⇒y=8α(α−3)
⇒y=8(α2−3α+49)−18
⇒y=8(α−23)2−18
So, Minimum value of y=−18 at α=+23