To solve this problem we need to use the triangle sum theorem. It states that the sum of the interior angles of a triangle is 180. We also know that the sum of the angle m and the unknown interior angle (angle C) is 180. Using this information we can conclude that the sum of the known interior angles (angles A and B) and m are both the same. It means that angle m is the sum of 36 and 90:
[tex]\begin{gathered} \measuredangle A+\measuredangle B=\measuredangle m \\ 90+36=\measuredangle m \\ \measuredangle m=126 \end{gathered}[/tex]
The answer is B.
