According to the given problem,
[tex]\angle7=131^{\circ}[/tex]
Note: When two lines are intersecting, then the pair of vertivally opposite angles are always equal.
Since the angles 1 and 7 are vertically opposite angles formed due to the intersection of lines 'p' and 'r'. So they must also be equal,
[tex]\begin{gathered} \angle1=\angle7 \\ \angle1=131^{\circ} \end{gathered}[/tex]
Thus, the angle 1 measures 131 degrees.
