Respuesta :

Answer: 9.8

Step-by-step explanation:

Since this is a right triangle, we can use the Pythagorean theorem to solve.

The Pythagorean theorem is: a² + b² = c² where a and b are the legs of the triangle and c is the hypotenuse (longest side, across from the right angle).

(DF)² + (FE)² = (DE)²

10² + d² = 14²

100 + d² = 196

100 - 100 + d² = 196 - 100

d² = 96

d ≈ 9.8 (rounded to one decimal place)