Which of the following could not be the measure of an exterior angle of a polygon?

a.) 60 degrees
b.) 2 degrees
c.) 153 degrees
d.) 191 degrees

Step-by-step explanation:

An exterior angle cannot be 191 degrees, because the sum of one exterior angle and one interior angle of a polygon must be 180°, and this options refers to a exterior angles that is above that restriction. So, 191° is the impossible option.

If you see the image attached, you will see that one exterior angles and one interior angle are on a straight angle which is always 180°. That's why a exterior angle cannot be more than 180°.

check above link.

graphically?   well, you graph them both, the solutions is where they both intersect each other, since there are two solutions, meaning they will meet twice, or namely the linear will run into the quadratic curve twice, and where they meet, those x,y coordinates are the solutions to the system.