A= 3400t + 600 | given formula
21000= 3400t + 600 | substitute the altitude into the formula
20400 = 3400 | subtract 600 from both sides
6 = t | divide both sides by 3400
6 minutes
If you didn't change the slope of the line, but you moved it
down 6 units on the graph, then its y-intercept would become
6 less. The equation of the new line would be ...
y = 1/3 x - 16 .
6......................................... i mean this is probably wrong but yeah
