You need to memorize and learne how to use the equation for position versus time:
For this problem for object A you have

= 5 m/s and

= 0. For object B you have

= 0 and

= 1 m/s^2. For both objects you have

= 0. When the objects meet both are at the same place - so set the equation for object A equal to the equation for object B- this will allow you to determine the time when they meet. Then shove that value for time back into one of the position equations to get
d. Check by putting that same value for time into the other position equation and see if you get the same value for
d.