Circle angles, trig, polar coordinates


Problem 1

Problem 2

In the picture above, if a, b, c are 60, 80, and 100 respectively, what is z?

Problem 3

Problem 4

Problem 5

What is x if the line is tangent to the circle?

Problem 6

If two sides of an angle are tangent to a circle, must the angle bisector contain the center of the circle?