Which characteristics will prove that DEF is a right, isosceles triangle?

the slopes of DE and EF are opposite reciprocals make the triangle Δ DEF a right triangle.

Step-by-step explanation:

The characteristics will prove that Δ DEF is a right isosceles triangle is the lengths of DE and EF are congruent, and their slopes are opposite reciprocals.

Now, the equal sides of DE = EF make the triangle Δ DEF an isosceles triangle and the slopes of two perpendicular lines are always the opposite reciprocals.

So the correct answer would be: The lengths of DE and EF are congruent, and their slopes are opposite reciprocals.

3< x< 5

step-by-step explanation:

|x - 4| < 1

there are two solutions, one positive and one negative.   remember to flip the inequality when taking the negative solution

x-4 < 1       x-4 > -1

add 4 to each side

x-4+4 < 1+4       x-4+4 > -1+4

x< 5                 x> 3

3< x< 5