题目如图,已知△ABC\triangle ABC△ABC和△ADE\triangle ADE△ADE,AB=ADAB=ADAB=AD,∠BAD=∠CAE\angle BAD=\angle CAE∠BAD=∠CAE,∠B=∠D\angle B=\angle D∠B=∠D,ADADAD与BCBCBC交于点PPP,点CCC在DEDEDE上.求证:BC=DEBC=DEBC=DE.知识点：相似三角形的判定I章节：图形的变化 / 图形的相似
如图,已知和,,,,与交于点,点在上.求证:.如图,已知和,,,,与交于点,点在上.求证:.如图,已知和,,,,与交于点,点在上.求证:.