The angles of a triangle always adds up to 180 degrees.
Hence, if you have the measures of 2 angles of a triangle, you can find the measure of the third angle by deducting the measures of the first 2 angles from 180 degrees.
30+100= 130
The sum of the measures of the first 2 angles of the triangle is 130 degrees.
180-130= 50
Ans: The measure of the third angle is 50 degrees.
