Final answer:
The equation y = 10 - 5x - 3x² is not linear because it contains a term with a variable raised to the power of 2 (x²), which makes it a quadratic equation.
Step-by-step explanation:
The equation y = 10 - 5x - 3x² is not linear because it contains a term with a variable raised to the power of 2 (x²), which makes it a quadratic equation. In a linear equation, the highest power of the variable is 1. The general form of a linear equation is y = mx + b, where m is the slope and b is the y-intercept.