Answer:
Following are the solution to this question:
Step-by-step explanation:
[tex]\angle AOB + \angle BOC = 180\\\\\angle MON = (\angle AOB + \angle BOC): 2 \\\\[/tex]
[tex]= 180: 2 \\\\=\frac{180}{2}\\\\= 90^{\circ}[/tex]
In point a:
[tex]\angle AOB = 60\\\\ \angle BOC = 120\\\\ \angle MON = (60 + 120): 2 \\\\[/tex]
[tex]= 180: 2 \\\\=\frac{180}{2}\\\\= 90^{\circ}[/tex]
In point b:
[tex]\angle BOC = 100\\\\\angle AOB = 80\\\\ \angle MON = (100 + 80): 2[/tex]
[tex]= 180: 2 \\\\=\frac{180}{2}\\\\= 90^{\circ}[/tex]
