This graph and table show the total number of cars parked in a parking lot, n, after it was open for t hours. Plot and table. Plot has horizontal axis from 0 to 3 in increments of 1, labeled t, and vertical axis from 0 to 18 in increments of 2, labeled n. Plot shows the points left parenthesis 0 comma 0 right parenthesis, left parenthesis 1 comma 6 right parenthesis, left parenthesis 2 comma 12 right parenthesis, and left parenthesis 3 comma 18 right parenthesis. Two-column table has column Time in hours left parenthesis t right parenthesis showing values 0, 1, 2, 3 and column Number of cars parked left parenthesis n right parenthesis showing values 0, 6, 12, 18.

What is an equation showing the relationship between n and t?

Enter your answer by filling in the box to complete the equation.
n =