1) a) Explain why, if triangle ABC has only acute angles, and the side lengths are a=BC, b=AC, and c=AB as usual, then a +b'>c'. Starting with such a triangle, show how to construct a region whose area is the difference between a +b- and c'. C 2) a) In the figure shown, the lengths AD=3 and DB=12. What are the lengths CD, AC, and CB? 90* 90* b) If the lengths are unknowns AD=x and DB=y, explain how D A B to find the same three lengths in part (a)