Driver Code
let x1 = - 1 ; let y1 = 2 ; let z1 = 1 ; let x2 = 0 ; let y2 = - 3 ; let z2 = 2 ; let x3 = 1 ; let y3 = 1 ; let z3 = - 4 ; let p = [ x1 , y1 , z1 ] ; let q = [ x2 , y2 , z2 ] ; let r = [ x3 , y3 , z3 ] ; equation_plane ( p , q , r ) ;