There was a surplus of office space in a city, with 400,000 square feet, or 16% of the total office space, vacant. how much office space did the city have?

step-by-step explanation:

once you graph it hit 2nd (the blue button) and graph

that takes you to a table of coordinates

on the left is x coordinates and on the right is y coordinates and an empty box

(you may have to scroll up/down in order to get ( x, 0)