What type of math is this?
Use the site called Desmos, it's a graphing calculator and should help you in all the ways you need. It isn't complex. Just put that equation in a box and it graphs it for you.
Answer:

Step-by-step explanation:
The table shows how the time it takes a train to travel between two cities depends on its average speed.
function models the time, y, in hours, that it takes the train to travel between the two cities at an average speed of x miles per hour
y represents the time
and x represents the average speed
WE know distance = speed * times
LEts find the distance using the table
distance = 32* 5= 160
40*4= 160
50*3.2 = 160
Time = distance / speed
times is y , distance is 160 and speed is x

If you would like to solve (n^3 - n^4) - (3n^3 - 7n^4), you can do this using the following steps:
(n^3 - n^4) - (3n^3 - 7n^4) = <span>n^3 - n^4 - 3n^3 + 7n^4 = n^3 - 3n^3 - n^4 + 7n^4 = -2n^3 + 6n^4
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The correct result would be <span>-2n^3 + 6n^4.</span>
You just literally mark the graph, you see the 1st points (2,12) go on the X axis to 2, then go up to 12 and mark that as a point. and continue with this tactic with the rest.