To add \(-\frac{8}{15} + \frac{4}{15}\), you simply combine the two fractions since they have the same denominator:
\[ -\frac{8}{15} + \frac{4}{15} = \frac{-8 + 4}{15} = \frac{-4}{15} \]
So the answer is:
\(-\frac{4}{15}\)
This corresponds to the response "−4/15 negative Start Fraction 4 over 15 End Fraction".