HELP PLS THIS IS HARD

In the proof of the triangle angle sum theorem, you must draw an auxiliary line. which construction must you use to draw this line?

Ben wants to play a carnival game that costs $2. in his pocket he has 5 red tickets worth 35 cents each, and 15 blue tickets worth 10 cents each. which of the following systems of inequalities correctly represents the constraints on the variables in this problem? let represent the red tickets and b represent the blue tickets.

Which of the following vectors are orthogonal to (2,1)? check all that apply