public Vector3 Solve33(Vector3 b)
{
float det = Vector3.Dot(Col1, Vector3.Cross(Col2, Col3));
Box2DXDebug.Assert(det != 0.0f);
det = 1.0f / det;
Vector3 x = new Vector3();
x.x = det * Vector3.Dot(b, Vector3.Cross(Col2, Col3));
x.y = det * Vector3.Dot(Col1, Vector3.Cross(b, Col3));
x.z = det * Vector3.Dot(Col1, Vector3.Cross(Col2, b));
return x;
}