Final answer:
Without more context or specific information from the distance vs. time table, the x-value of 900 cannot be determined.
Step-by-step explanation:
To determine the x-value of 900 in the distance vs. time table, we need to look at the table and find the corresponding x-value for 900. From the information provided, it is not clear how the table is organized or what the units are for distance and time. Therefore, without more context or specific information from the table, we cannot determine the x-value of 900.