Find an equation of the set of all points equidistant from the points a(−1, 6, 3) and b(4, 3, −2).

Hello :
the set of all points M (x,y) equidistant from the points A(−1, 6, 3)
and B(4, 3, −2): 
MA = MB  or  MA² = MB²
an equation is : 
(x+1)²+(y -6)²+(z - 3)² = (x - 4)² +(y -3)² + (z+2)²