To find the value of the function \( y = \frac{1}{8x - 13} \) when \( x = -4 \), we can substitute \(-4\) for \(x\):
\[ y = \frac{1}{8(-4) - 13} \]
Now, calculate \(8(-4)\):
\[ 8(-4) = -32 \]
Now substitute this value back into the equation:
\[ y = \frac{1}{-32 - 13} \]
Next, calculate \(-32 - 13\):
\[ -32 - 13 = -45 \]
So, we have:
\[ y = \frac{1}{-45} \]
This simplifies to:
\[ y = -\frac{1}{45} \]
Now, let's evaluate if \(-\frac{1}{45}\) matches any of the options provided. Since none of the offered options of \(-15\), \(-12.5\), \(-13.5\), or \(-16\) match \(-\frac{1}{45}\), it appears that there may be an error in interpreting the function or the choices available don't correspond to the computed value.
Thus, based on calculations for \( x = -4 \):
\[ y \approx -0.0222 \]
This confirms no given option matches. Please review the function and available choices again!