Equation of the line through (1, -2, 3) parallel to the line 2x​ = 3y​ = −6z−1​ is 2x−1​ = 3y+2​ = −6z−1​ = r (say) ... (1) Then any point on (1) is (2r + 1,3r -2, -6r + 3) If this point lies on the plane x - y + z = 5 then (2r + 1) - (3r - 2) + (-6r + 3) = 2 ⇒ r = 71​ Hence the point is (97,7−11​,715​) Distance between (1, -2, 3) and (97,7−11​,715​) = 494​+499​+4936​​ = 4949​​ = 1