We are asked to find the measure of angle ABC and classify the angle.
As you can see from the figure, vertex A is at 30° and vertex C is at 155°
So, the angle ABC is
[tex]\angle ABC=155\degree-30\degree=125\degree[/tex]So, the angle ABC is 125°
Now recall that an obtuse angle is greater than 90° and less than 180°
Since 125° is between 90° and 180°, therefore, the angle ABC is an obtuse angle.
[tex]m\angle ABC=125\degree,\quad obtuse[/tex]