Let point P‌quad be the intersection of lines r=(i+2j−k)+λ(2i+3j+4k) r=(−i−3j+7k)+µ(i+2j−k) and Thus, 2λ+1=µ−1 3λ+2=−3+2µ And 4λ−1=7−µ On solving the above equations, λ=1 µ=4 Thus the required point of intersection is, P=(3i+5j+3k)