Which equation could have been used to create this function table?

a. y = x + 1

b. y = 2x

c. y = x

d. y = x + 10

It would be c. y = x because if you plug in the numbers, it would be true

So if you look at the table, you see that when x = 9, y = 9.  This continues all the way down the table.  So you can determine that x = y (the x values are the same as the y values).