The line passing through the points 5,1,a,3,b,1 crosses the  yz-plane at the point  0,172,−132then

The yz-  plane cuts the line segment joining the points  Ax1,y1,z1,Bx2,y2,z2in the ratio−x1:x2Hence, the   yz-plane divides the line segment joining the points 5,1,a,3,b,1in the ratio  5:3externally Hence the point of division is  0,5b−32,5−3a2=0,172,−132Equate the corresponding coordinates, we get  a=6,b=4