∫∠BCA = 90 BC =3 AB=6.

According to Pythagorean Theorem, the length of AC is three times that of root number 3 of 3.

At △CED

CD=AD-BC=AB-BC=6-3=3

CE=x

ED=3 times the root number 3-x

Then, according to Pythagorean theorem, it is found that the length of DE is root number 3.

Hope to adopt, thank you-