function muladd( alpha, x, y ) {
	var v = addon( alpha, x, y );
	return new Complex128( v.re, v.im );
}
Performs a multiply-add operation involving three double-precision complex floating-point numbers.

@private
@param {Complex128} alpha - complex number
@param {Complex128} x - complex number
@param {Complex128} y - complex number
@returns {Complex128} result

@example
var Complex128 = require( '@stdlib/complex/float64/ctor' );

var z1 = new Complex128( 5.0, 3.0 );
var z2 = new Complex128( -2.0, 1.0 );
var z3 = new Complex128( 7.0, -8.0 );

var out = muladd( z1, z2, z3 );
// returns <Complex128>[ -6.0, -9.0 ]