Question 83353
Well, a triangle has to add up to 180 degrees in angles, right? So, lets see what we can do!

If to top angle was 50, the two other angles have to be half of the range between 50 and 180 because it's an isoceles triangle and so we get one for each of the following angles.

180-50=130/2=65


A is the top so B and C have to both be 65... If A can be anything, then you can do another technique.

Make it at the bottom and pretend it's one of those two angles...  you have to multiply the 50 by 2 and get 100 and then subtract that from 180 so the top angle is 80.


PLEASE READ:
The top one is only if A is strictly the top angle.

Both of them are if A can be any angle.