Convert the angle in degrees to radians.
Consider a circle of radius r. A central angle of a revolution (360°) will subtend an arc equal to the circumference of the circle. Because the circumference of the circle equal 2πr, we see that 360° = 2π radians, or 180° = π radians.
Converting form degrees to radians can be summarized as follows.
1 degree = radian
Now convert the given angle in degrees to radians. Use the formula from above to write 1 degree in radians.
-19° = -19 * 1 degree
= -19 * radian
Simplify. Remember that π 3.1416.
-19° = -19*radian
– 0.33 radian