证明全等
如图http://hi.baidu.com/r%5Fwo/album/%BB%AD%D6%D0%C3%C0%C8%CB/19b4ef114774cfc6a6ef3f62.htmlC'D'是高，AC=A'C',CD=C'D',∠ACB=∠A'C'B',求证：△ABC≌△A'B'C'．
参考答案:证明：
AC=A'C',CD=C'D',∠ADC=∠A'D'C'=90
所以，△ADC≌△A'D'C',(H.L)
所以,∠A=∠A',AC=A'C',,∠ACB=∠A'C'B',
△ABC≌△A'B'C'．(ASA)