结论：MN=AM+BN因为∠ACB=90度,MN是条直线,所以∠ACM+∠NCB=90度又BN⊥MN,故在Rt△BNC中,∠CBN+∠NCB=90度所以,∠ACM=∠CBN又AM⊥MN,故而,在Rt△AMC与Rt△CNB中,∠AMC=∠CNB=90度,∠ACM=∠CBN,AC=CB所以Rt△AMC≌Rt...