Final answer:
The function y = x⁵ is nonlinear because it does not follow the form of a linear equation and its graph will be a curve, not a straight line.
Step-by-step explanation:
The function y = x⁵ is a nonlinear function. According to the definition of linear equations, which are of the form y = a + bx, where a is the y-intercept and b is the slope, a linear equation graphs as a straight line. In contrast, the function y = x⁵ has an exponent on the x term which is higher than 1, indicating that the graph of this function will not be a straight line but a curve that changes slope as x changes, which is characteristic of nonlinear functions.