题目如图,∠DCE=90∘\angle DCE=90^{\circ}∠DCE=90∘,CD=CECD=CECD=CE,AD⊥ACAD\bot ACAD⊥AC,BE⊥ACBE\bot ACBE⊥AC,垂足分别为AAA、BBB.试说明AD+AB=BEAD+AB=BEAD+AB=BE.知识点：全等三角形的判定与性质章节：未标注
如图,,,,,垂足分别为、.试说明.如图,,,,,垂足分别为、.试说明.如图,,,,,垂足分别为、.试说明.