Final answer:
The V6 electrode should be placed in the fifth intercostal space at the left midaxillary line for a standard 12-lead EKG on a 9-year-old patient.
Step-by-step explanation:
An EKG technician performing a standard 12-lead EKG on a 9-year-old patient should place the V6 electrode in the fifth intercostal space at the left midaxillary line. The placement of electrodes during an EKG is crucial for obtaining accurate readings of the heart's electrical activity. With the correct placement, the EKG can yield comprehensive information about heart function and assist in diagnosing various heart conditions.