AD A撇D撇分别是三角形ABC和三角形A撇B撇C撇的高 AB=A撇B撇 AD=A撇D撇 BC=B撇C撇 求证AC=A撇C撇

解：RT△ADB和RT△A'D'B'中 ∠ADB=∠A'D'B'；AD=A'D'；AB=A'B' RT△ADB≌RT△A'D'B'得到BD=B'D' BC=B'C',CD=BC-BD,C'D'=B'C'-B'D' CD=C'D',RT△ADC和RT△A'D'C'中 ∠ADB=