Find the unit rate

A fertilizer covers 5/6 square foot in 1/4 hour

Agrid shows the positions of a subway stop and your house. the subway stop is located at (-5,2) and your house is located at (-9,9). what is the distance, to the nearest unit, between your house and the subway stop?

Can you explain how a table can be used to find a rate of change?

Me because i don't understand how to do it.: )