Answer:

Step-by-step explanation:
Suppose we have a triangle WXY whose internal angles are:



The sum of the measures of the angles must be 180°, thus:

Simplifying:
15x + 15 = 180
Subtracting 15:
15x = 165
Dividing by 15:
x = 11
Thus, the measure of angle Y is


360° = 2π
2 = 360° / π
1 rad = 360° / 2π