Hey Guys!

For number 39, I do not understand how to get answers B and C. I understand that for angle T, B = 20. Since both sides are congruent, the angles opposite these sides are also congruent. Now angle T = 80 because 80+80 = 160 + 20 = 180.

I do not understand how part B is 100 and part C is 40. Can somebody clarify these for me? Thanks.