Is 2 A Solution For Y-8>2y-4?

The solution to the inequality can be found as follows.
y - 8 > 2y - 4
-8 > y -4    (subtract y from both sides)
-4 > y    (add 4 to both sides)
y < -4    (rearrange to use < symbol*)

Your proposed solution (2) is not less than -4, so 2 is not a solution.
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* Some people find this helpful, as it puts the expression in the order you see the numbers on a number line. In this case, valid solutions for y will be to the left of -4 on the number line. That is, they will be less than -4. You see that y is left of -4 when we use the < symbol.