Question

In circle L, JK is a tangent and PM is a diameter. Find the measure of arc MN. Show all work http://assets.openstudy.com/updates/attachments/514b8b8fe4b07974555dfe7e-rvjack-1363905640202-07_09h_04.gif

Answer 1

heelp

Answer 2

The theorem is needed:
Note that arc PJ + arc JM = 180 because of the diameter.

So, arc JM = 180 - arc PJ = 180 - 3b. -->

Now, read how to find the measure of an angle formed by two secants drawn to a circle from an outside point.

Answer 3

Angle JKP = 1/2( arc JM - arc JP)

20 = 1/2 ((180-3b) - 3b)

40 = 180 - 6b

@rvjack --> Solve for b and post your answer. There is more work to be done after that.