Question

a weathervane is pointing north. after the wind changes direction, the weathervane points east. the turn forms a right angle. how many degrees did the arrow turn? 90° you can name the turn ∠nve, because it connects points n, v, and e in order. what is another good name you could use for ∠nve? ∠n ∠v ∠evn ∠evs

Explanation:

When naming an angle, we can use the vertex letter in the middle. In \(\angle NVE\), \(V\) is the vertex. Another valid name is \(\angle EVN\) as it also has \(V\) as the vertex and uses the same three points \(E\), \(V\), and \(N\) (just in reverse order). \(\angle N\) is not correct because \(\angle N\) would imply the vertex is \(N\) which is not the case. \(\angle V\) is too ambiguous as there are multiple angles at point \(V\). \(\angle EVS\) refers to a different angle (between \(E\), \(V\), and \(S\)) which is not the right - angled turn from \(N\) to \(E\).

Answer:

\(\angle EVN\)