Equation of sphere
x2+y2+z2+2ux+2vy+2wz+d=0
It passes through
(3,0,0) 9+6u+d=0 .....(i)
(0,−1,0) (1−2v+d=0 ....(ii)
(0,0,−2) 4−4w+d=0 ....(iii)
Also centre (−u,−v,−w) lies on the plane
3x+2y+4z=1
−3u−2v−4w=1 .....(iv)
By solving equations (i), (ii), (iii), and (iv)
We get u=−43
v=0
w=34
d=−1
then putting the values of u, v, w, d in the above equation
6(x2+y2+z2)−16x+9z−6=0.