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Not if their shafts are not connected together. Differences in load and slight differences in motor characteristics will always cause one to run at a different speed from the other with the same input voltage.
If both motors are identical and have the shafts coupled together and are fed by the same power source they will act just like a 10 amp motor instead of a 5 amp motor.
I have seen industrial conveyors and process equipment do this with matched pairs of motors for loads that require a high capacity power source only part of the time. At light loads one motor is shut off and just free wheels.