For finding the z - intercept put x = 0 and y = 0
float z = - D / C ; rslt [ 0 ] = x ; rslt [ 1 ] = y ; rslt [ 2 ] = z ; return rslt ; } void equation_plane ( int p [ ] , int q [ ] , int r [ ] ) { int x1 = p [ 0 ] ; int y1 = p [ 1 ] ; int z1 = p [ 2 ] ; int x2 = q [ 0 ] ; int y2 = q [ 1 ] ; int z2 = q [ 2 ] ; int x3 = r [ 0 ] ; int y3 = r [ 1 ] ; int z3 = r [ 2 ] ;