The equation of the line passing through the points (2,3,5),(1,−2,1)
x−21=y−35=z+1−4
x−2−1=y−3−5=z+5−4
x+21=y+35=z+54
x−21=y−35=z−54
Equation of a line passing through the points A(x1,y1,z1) and B(x2,y2,z2) is x−x1x2−x1=y−y1y2−y1=z−z1z2−z1
Therefore, the equation of the line passing through the points (2,3,5),(1,−2,1) is x−21=y−35=z−54