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After spending some time guessing what is written in your post, I know the answer.
Yes, the data is linear.
For each increase of x by 4 units the variable y response decreases by 5 units:
= -2 - , i = 1, 2, 3, 4.
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Let me show you how to formulate it in a right way:
Whether the relationship shown in the table is linear ?
x -9 -5 -1 3
y -2 -7 -12 -17
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Notice that using the "space" between the numbers is necessary to show a sequence in a right way.
Using the space in combination with the comma is even better.