Answer is 0
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Step-by-step explanation:
Pick any two points on the line. Let's say you pick the two points (0,6) and (2,6).
Use the slope formula
m = (y2-y1)/(x2-x1)
m = (6-6)/(2-0)
m = 0/2
m = 0
The slope of the line is 0. For any flat horizontal line like this, the slope is always 0.
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Alternative approach:
The slope is equal to the rise over run
slope = rise/run
The rise tells us how much the line goes uphill or downhill as you move from left to right. In this case, there is no up or down movement. So the rise = 0. The run can be anything you want. I'll let run = 1.
We have
slope = rise/run = 0/1 = 0