(1) Because of folding, angle A equals angle ABD equals 40 degrees, because triangle ABC is a right triangle, angle ABC equals 50 degrees, and angle ABC equals angle ABD+ angle BCD, so angle BCD equals 10 degrees. (2) Because right triangle, AC=8, BC=6, so AB =/kloc-. Sin angle A=BC/AB =6/ 10=3/5, so cos angle A=4/5=AE/AD. AE=5 is known. So AD=25/4(3) Because of folding, AD=BD, and the perimeter of the triangle BCD =CD+BC+BD=AC+BC. Because it is a right triangle, using Pythagorean theorem, the square of AC+the square of BC = the square of m, and because the area of triangle ABC is equal to m+ 1, it can be found that the square of AC +BC = the root sign (m+4m+2 ~) is adopted by LZ.