Would sram X3 shifters work with a sram X7 derailleur?

Yes, SRAM X3 shifters can work with a SRAM X7 derailleur, as both are designed to operate within the SRAM 1:1 actuation ratio system. However, it's essential to ensure that the shifters and derailleur are compatible in terms of speed (e.g., both being 7-speed or 8-speed). While they can function together, performance may not be optimal compared to using components from the same series.