Look at the right end behavior of each function )\(as x -> infinitey). what about the function determines whether its graph wil point up or down on the right-hand side?

Answer 1

If the first term is a x^n it dominates the terms in smaller powers of x as x becomes large. Therefore just look at that first term. For example
5 x^15 + 3 x^12 + 6 x^7 etc
just look at
5 x^15
that is big y up as x gets big, so it goes up to the right
if it started with -5 x^15 , it would go down to the right

Answer 2

Even positive