To determine the instantaneous position of an object using an acceleration-time graph, calculate the area under the curve to find the change in velocity over specific time intervals. This change in velocity can then be integrated to find the corresponding change in displacement using a velocity-time graph. The initial position and velocity must be factored in to arrive at the final position. While there isn't a single formula for this process, the relationship between acceleration, velocity, and displacement is crucial. Understanding these concepts allows for accurate position calculations from an acceleration-time graph.