\[отрицательное;\]
\[\frac{14b - b^{2} - 50}{b^{2} + 2b + 1} =\]
\[= - \frac{b^{2} - 14b + 50}{(b + 1)^{2}} =\]
\[= - \frac{(b - 7)^{2} + 1}{(b + 1)²}\]