DNIWE.cs

public class SomeCalcController : Controller
{
	public ActionResult DoCalc(SomeCalc calc)
	{
		calc.DoCalc();
		
		calc.Save();
	}
}

public class SomeCalc
{
	public double X { get; set; }
	
	public double Y { get; set; }
	
	public void DoCalc()
	{
		// ...
	}
	
	public void Save()
	{
		SomeCalcDAL dal = new SomeCalcDAL();
		
		dal.SaveCalc(this);
	}
}

public class SomeCalcDAL
{
	public SomeCalcDAL() { }
	
	public void SaveCalc(SomeCalc calc)
	{
		CalcDbContext db = new CalcDbContext();
		
		db.Calculations.Add(calc);
		
		db.SaveChanges();
	}
}

public class CalcDbContext : DbContext
{
	public DbSet<SomeCalc> Calculations { get; set; }
	
	public CalcDbContext() { }
}