Line joining the points (1,−1,1) and (1,1,−2) be ‌x−1∕0=‌y+1∕2=‌z−1∕−3 Line joining the points (2,1,−6) and (3,−1,−7) is ‌x−2∕1=‌y−1∕−2=‌z+6∕−1 For intersection of points, ‌‌x−1∕0=‌y+1∕2=‌z−1∕−3=K ‌⇒x=1,y=2K−1‌ and ‌Z=−3K+1 and ‌x−2∕1=‌y−1∕−2=‌z+6∕−1=λ ‌x=λ+2,y=1−2λ,z=−λ−6 ‌∴λ=−1‌ and ‌K=2 ∴ Positivion vector of points of intersection is i+3