Respuesta :

Answer:

x = 20 / √3 = 20√3 / 3

Step-by-step explanation:

AC² = AD² + BC² = x² + x² = 2 x²

AF² = AC² + CF² = 2 x² + x² = 3 x²

3 x² = 20² = 400

x² = 400/3

x = 20 / √3 = 20√3 / 3