Answer:
f(u +6) = u
Step-by-step explanation:
Put (u+6) in place of t and simplify:
f(u+6) = (u+6) -6
f(u+6) = u
Answer:
34 feet
Step-by-step explanation:
418 - 384 = 34 feet above sea level
So the expression is:

You can combine like terms, which are terms that contain the same variables raised to the same power. That means you can combine the two

.

The other terms can't be combined.
Your final answer should be

.