Answer every question plz

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

Find x & pleeeeaaaassseeee me !

Ascatterplot is produced to compare the size of a school building to the number of students at that school who play an instrument. there are 12 data points, each representing a different school. the points are widely dispersed on the scatterplot without a pattern of grouping. which statement could be true