Question

The equation y = ax describes the graph of a line. If the value of a is negative , the line:

A. goes up and to the right.
B. is horizontal.
C. is vertical.
D. goes down and to the right.

Answer 1

If the equation y = ax describes the graph of a line and the value of a is negative, then the line goes down as x increases or up as x decreases. This means that the line is decreasing from left to right, which corresponds to option D: the line goes down and to the right.

Option A, "goes up and to the right," is incorrect because a negative value for a means the line is decreasing, not increasing, as x increases.

Option B, "is horizontal," is incorrect because if a is negative, the line cannot be horizontal.

Option C, "is vertical," is incorrect because y = ax is not an equation of a vertical line.