Question

what is a simple way to tell that $1\frac{1}{4}$ is not the slope of the graph?
the y-intercept is $2\frac{1}{3}$, not $1\frac{1}{3}$.
a slope cannot be a mixed number
the line slants downward, so the slope is negative.
the change in x from a to b is negative

Explanation:

To determine why \(1\frac{1}{3}\) is not the slope, we analyze the graph's line. A line slanting downward has a negative slope. \(1\frac{1}{3}\) is positive, so the option stating "The line slants downward, so the slope is negative" explains why \(1\frac{1}{3}\) (positive) can't be the slope. Other options: y - intercept is irrelevant to slope sign, slope as mixed number is allowed (e.g., \(1\frac{1}{2}\) as slope), and change in x sign doesn't directly relate to slope sign here.

Answer:

The option: "The line slants downward, so the slope is negative" (the bottom - middle option among the four choices).