According to the given picture, the angle that is not named is the supplement of 139°:
[tex]\begin{gathered} \measuredangle2+139=180 \\ \measuredangle2=180-139 \\ \measuredangle2=41 \end{gathered}[/tex]
Now, we can use the triangle sum theorem to find the measure of angle 1.
[tex]\begin{gathered} 41+83+\measuredangle1=180 \\ 124+\measuredangle1=180 \\ \measuredangle1=180-124 \\ \measuredangle1=56 \end{gathered}[/tex]
Angle 1 measures 56°.
