Question

HELP!!! On a piece of paper, use a protractor to construct a triangle with angle measures of 30° and 50º. What is the measure of the third angle?

Answer 1

sum of all angles in a triangle must equal 180

so 

180 - (30 + 50)
= 180 - 80
= 100

answer:
third angle = 100

Answer 2

Remember that all of a triangle angles have to add up to 180 degrees. In that case, let's solve!: 30+50=80     180-80= 100

So the third angle is equal to 100. I hope this helped!!