Answer: D. 8/5
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Explanation:
This is a proportional relationship which means that y/x= k .The y value divided by the x value will give you k which is the slope or in other words the constant variable.
So just divide the y value by the x value to find the k.
(5,8)
The y value is 8
The x value is 5
8/5 = k
k = 8/5