Answer:
50 degrees
Explanation:
All the angles in a triangle must add up to 180 degrees
a+b+c=180
Substitute 30 in for a, and 100 in for b
30+100+c=180
Combine like terms
130+ c=180
Subtract 130 on both sides
c=50
So, the third angle is 50 degrees
Hope this helps! :)