Final answer:
The equation y = -x + 15 is a linear equation since it fits the standard form y = a + bx, where a is the y-intercept and b is the slope. The line slopes downward to the right due to the negative slope (-1).
Step-by-step explanation:
The equation y = -x + 15 can be analyzed in the context of the standard form for a linear equation, which is y = a + bx. Here, a represents the y-intercept and b is the slope of the line. In our equation, b, which is -1 (the coefficient of x), denotes a slope that is negative, implying the line slopes downward to the right. Since this is in the form of a linear equation and the graph would be a straight line, the correct answer to the question is (b) Linear.