Perform sum by unique identifier

[Ravermax]

I have two spreadsheets, the Sales spreadsheet that has the columns ID_Sales, Value_Sale and a second spreadsheet Products that has the columns ID_Sales, Product, Value_Unitary.

I want to combine the spreadsheets so that the graphs interact with each other.
When performing the combination, Value_Sale creates several references, and I cannot use it as a metric.
How do I create a formula to add only the Value_Sale with unique ID_Sales.

[sam8]

I'm not quite following the problem. Based on what you've said so far, it sounds like you would want to create a blend of the two spreadsheets, joining on ID_Sales. What isn't working well about that?