The inequality that explains why the three segments cannot be used to construct a triangle is ED + EF < DF
From the question, we are to determine which of the given inequalities explains why the three segments cannot be used to construct a triangle
From the given information,
Line DE is about half the length of line DF
That is,
ED = 1/2 DF
Also,
Line FE is about one-third of the length of line DF
That is,
EF = 1/3 DF
Then, we can write that
ED + EF = 1/2DF + 1/3DF
ED + EF = 5/6 DF
Since,
5/6 DF < DF
Then,
ED + EF < DF
Hence, the inequality that explains why the three segments cannot be used to construct a triangle is ED + EF < DF
Learn more on Inequalities here: https://brainly.com/question/1447311
#SPJ1