If the object is moving with constant velocity, then the instantaneous velocity at every moment, the average velocity, and the constant velocity are all the same. In the image above, the red line is t...If the object is moving with constant velocity, then the instantaneous velocity at every moment, the average velocity, and the constant velocity are all the same. In the image above, the red line is the position vs time graph and the blue line is an approximated slope for the line at t=2.5 seconds. For constant velocity motion, the slope gives the constant velocity, the average velocity, and the instantaneous velocity at every point.