[c#] inner join in linq to entities

I have entity called Customer and it has three properties:

public class Customer {
    public virtual Guid CompanyId;
    public virtual long Id;
    public virtual string Name;
}

I have also entity called Splitting and it has three properties:

public class Splitting {
    public virtual long CustomerId;
    public virtual long Id;
    public virtual string Name;
}

Now I need to write a method that gets companyId and customerId. The method should return list of splitting that relates to the specific customerId in the companyId. Something like this:

public IList<Splitting> get(Guid companyId, long customrId) {    
    var res=from s in Splitting 
            from c in Customer 
            ...... how to continue?

    return res.ToList();
}

public IList<Splitting> get(Guid companyId, long customrId) {    
    var res=from c in Customers_data_source
            where c.CustomerId = customrId && c.CompanyID == companyId
            from s in Splittings_data_srouce
            where s.CustomerID = c.CustomerID
            select s;

    return res.ToList();
}

You can find a whole bunch of Linq examples in visual studio. Just select Help -> Samples, and then unzip the Linq samples.

Open the linq samples solution and open the LinqSamples.cs of the SampleQueries project.

The answer you are looking for is in method Linq14:

int[] numbersA = { 0, 2, 4, 5, 6, 8, 9 };
int[] numbersB = { 1, 3, 5, 7, 8 };

var pairs =
   from a in numbersA
   from b in numbersB
   where a < b
   select new {a, b};

Not 100% sure about the relationship between these two entities but here goes:

IList<Splitting> res = (from s in [data source]
                        where s.Customer.CompanyID == [companyID] &&
                              s.CustomerID == [customerID]
                        select s).ToList();

IList<Splitting> res = [data source].Splittings.Where(
                           x => x.Customer.CompanyID == [companyID] &&
                                x.CustomerID == [customerID]).ToList();