29. Prove that the following systems intersect at a point and then determine the solution: П₁: 2x + y + 6z - 7 = 0 π1: П2: 3x+4y+3z+8=0 П3 x 2y 4z - 9 = 0 (x = 1-2t 27. In 3-space, find the distance between the skew lines y=1+t and [x, y, z] = [4, 7, 1] + t [1, 4, 2]. z = 4t (x = 7-t 28. Determine the intersection point of the line y = 2+t and the plane π: x + 2y + 3z − 15 = 0 (z = 4 - 3t