1. If the vertex f of □ is also on a semicircle, the center of the semicircle with diameter AB is located at the midpoint of GD, the side length of □DEFG is 2a, and the radius of the semicircle with diameter AB is the root sign (2a)? Add an a? Is equal to the root number 5a, and the ratio of the radius of the semicircle to the side length of □DEFG is the root number 5a: 2a = the root number 5: 2.

2. If the area of □DEFG is 100 and ED= 10 connects AE and BE, then ∠ AE, be = 90 and DE cross the center o of the inscribed circle of △ABC, and ED ⊥ AB ∴△ AED ∽△ EBD. +BC？ =AB？

Get (AD+4)？ +(BD+4)？ =(AD+BD)？ , simplified as: AD×BD=4AD+4BD+ 16, AD×BD=ED? = 100 so AD+BD=2 1, and the diameter of the semicircle AB=2 1.

Give it to me.