Use the horizontal line test to determine whether the function is one-to-one. y = √x+5-1 y= Ay Is the function one-to-one? O No Yes

OTHER APPLICATION Attitude Change Social psychologist have found that as the discrepancy between the view of a speaker and those of an audience increase to a point but decrease when the discrepancy becomes too large particular if the communicator is viewed by the audience as having low credibility, Suppose that the degree of change can be approximated by the function D(x)=x4+8x3+80x2 Where x is the discrepancy between the view of the speaker and those of the audience as measure by score on a question-naira. Find the amount of discrepancy the speaker should aim for to maximize the attitude change in the audience. Source: Journal of Personality and Social Psychology.

Explain how to find the input variable in a word problem that uses a linear function.