Answer
-3.9kcal/mol. Exergonic.
Work Step by Step
To find the net $\Delta$, add the $\Delta$ values for the two coupled reactions, which really make one overall reactions when coupled. Negative $\Delta$ values mean that reactions will be spontaneous/exergonic, releasing free energy. That is what the large free energy release from ATP hydrolysis does, make non-spontaneous reactions spontaneous by coupling.