To solve the equation \( \frac{2}{8}y + 9 = 8 \), we can first simplify the fraction:
\[ \frac{2}{8} = \frac{1}{4} \]
So the equation can be rewritten as:
\[ \frac{1}{4}y + 9 = 8 \]
Next, we can isolate the term with \( y \) by subtracting 9 from both sides:
\[ \frac{1}{4}y = 8 - 9 \] \[ \frac{1}{4}y = -1 \]
To solve for \( y \), we can multiply both sides by 4:
\[ y = -1 \times 4 \] \[ y = -4 \]
Thus, the solution is:
\[ \boxed{-4} \]