Yes this is a function
The reason why is because the x coordinates do not repeat. Each x value maps to exactly one y value. For any input, there is exactly one output. If you were to graph all of these points, then the graph would pass the vertical line test.
If we had something like (2,4) and (2,0) then the input x = 2 would lead to multiple outputs (y = 4, y = 0) which would not make it a function; however we don't have any repeated x values here.
(s o t)(-7) = s(t(-7)) = s(3(-7)) = s(-21) = 2 - (-21)^2 = 2 - 441 = -439
Answer: No eror
Step-by-step explanation:
Answer:
It’s 60miles
Step-by-step explanation:
We assume the trip is "d" miles and that the "extra hour" refers to the additional time that a current of 2 mph would add. That is, we assume the reference time is for a current of 0 mph.
The time with no current is ...
time1 = distance/speed
time1 = d/12 . . . . hours
With a current of 2 mph in the opposite direction, the time is ...
time2 = d/(12 -2) = d/10
The second time is 1 hour longer than the first, so we have ...
time2 = 1 + time1
d/10 = 1 + d/12
6d = 60 + 5d . . . . multiply by 60
d = 60 . . . . . . . . . subtract 5d
The one-way distance is 60 miles.