31) VAM =

\(\angle VAM = \angle ZAM - \angle ZAV\)

\(\angle ZAV\) = 180° - \(\angle ZAB\) - \(\angle BAV\) = 180° - 40° = 140°

\(\angle ZAM\) = 180° - \(\angle ZAB\) - \(\angle BAM\) = 180° - 70° = 110°

\(\angle VAM\) = 110° - 140° = 30°

Ответ: 30°