Hello there!
Use the slope formula:
m=
![(y2-y1)/(x2-x1)](https://img.qammunity.org/2022/formulas/mathematics/high-school/o9cj8rzlmrloqj7wwadpz47qesxrup4k3e.png)
Now, plug in all the values:
![(9-9)/(6-(-8)) \\(0)/(6+8) \\0](https://img.qammunity.org/2022/formulas/mathematics/high-school/4tv0c9uwgatckqzfycvyp81redra1dvjrs.png)
The slope is 0. Why?
If we are given 2 points and their y-coordinates are the same, then the line is a horizontal line. Its rise is zero.
Another formula for Slope is Rise/Run. If the rise (the amount of units we move up) is 0, then the slope is 0.
Therefore, the slope is 0.
Hope this helps you!
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