The slope of the line is
![m=0](https://img.qammunity.org/2021/formulas/mathematics/middle-school/ejo7v6f8apqzf3aovi8oslh98eb9n0jrik.png)
Step-by-step explanation:
Given that the line contains the points (-1,9) and (9,9)
We need to determine the slope of the line.
Slope:
The slope of the line can be determined using the formula,
![m=(y_2-y_1)/(x_2-x_1)](https://img.qammunity.org/2021/formulas/mathematics/middle-school/e9lgdayfzr27dyurvzbw9lffpiv7535tiv.png)
The slope of the line can be determined by substituting the points (-1,9) and (9,9) in the above formula.
Thus, substituting the values, we have;
![m=(9-9)/(9+1)](https://img.qammunity.org/2021/formulas/mathematics/middle-school/7uo0b6dlcvufj7ypox658lj0rr2hbrl99h.png)
Simplifying, we get;
![m=(0)/(10)](https://img.qammunity.org/2021/formulas/mathematics/middle-school/wmsha2s3m9ltiekze8wdk6wsziqaxf5u0o.png)
![m=0](https://img.qammunity.org/2021/formulas/mathematics/middle-school/ejo7v6f8apqzf3aovi8oslh98eb9n0jrik.png)
Thus, the slope of the line is
![m=0](https://img.qammunity.org/2021/formulas/mathematics/middle-school/ejo7v6f8apqzf3aovi8oslh98eb9n0jrik.png)