Is the function y = 5 + (7/4)x² – 8x linear or nonlinear?

The function ( y = 5 + frac{7}{4}x^2 – 8x ) is nonlinear.

Explanation: A linear function can be written in the form ( y = mx + b ), where ( m ) and ( b ) are constants, and the highest exponent of ( x ) is 1. In this function, the term ( frac{7}{4}x^2 ) has ( x ) raised to the power of 2, which makes it a quadratic term. Thus, this function represents a parabola and is considered nonlinear.