Answer:
D E + E F greater-than D F
5 less-than D F less-than 13
Triangle D E F is a scalene triangle
Step-by-step explanation:
we know that
The Triangle Inequality Theorem states that the sum of any 2 sides of a triangle must be greater than the measure of the third side
we have the triangle EDF
where

<u><em>Applying the triangle inequality theorem</em></u>
1)

2)

so
The length of DF is the interval -----> (5,13)
The triangle DEF is a scalene triangle (the three length sides are different)
therefore
<em>The statements that are true are</em>
D E + E F greater-than D F
5 less-than D F less-than 13
Triangle D E F is a scalene triangle