Solution: Starting from point A, AE is perpendicular to BC, the vertical foot is E, and then starting from point A, AF is perpendicular to the extension line and F of DB.

From the title, we can know that the angle ABC = 30, DBC = 90° and ACB = 45°.

That is, the angle FBA = 60, AF= FB 3 times the root sign, and FB =1/2ab = 60.

So AF=60 times the root number 3. And FD = FB+BD = 60+100 =160.

Then in the triangle AFD, the square of Pythagorean theorem AD = the square of AF+the square of FD. AD=20 can get the root number 9 1.

Similarly, AE=60 can be calculated. Because the angle ACE=45, AC=60 times the root number 2.