Answer:
40 degrees
Step-by-step explanation:
The angles of a triangle add up to 180 degrees. If you add the second triangles given angles together you get 100 degrees. This means that the third angle must be 80 degrees as
180 - 100 = 80
So now, you know the the angles for the first triangle are 60 and 80 degrees. To find the missing angle, subtract the total angle degrees by the amount known;
60 + 80 = 140
180 - 140 = 40
