Answer:
B) y = 10x
Explanation:
It should not be too hard for you to determine that every number on the bottom row is the same as the number on the top row with a zero appended.
Appending a zero to a number is the same as multiplying it by 10. For example, ...
... 90 = 10ยท9
... y = 10x
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In case that observation doesn't work out for you, you can always solve the given equation for k, then choose values from the table to fill in.
... y = kx
... k = y/x . . . . . divide by the coefficient of k, which is x
Fill in values from the table
... k = 20/2 = 10 . . . . . . from the second column
Now put this value where k is in the equation. After you do that, you know ...
... y = 10x