1)CD+DE=EB
2)AC+CD=DE+EB
3)3AC=2AB
1)式代入2)得AC+CD=CD+DE+DE,求槐册塌铅圆得姿喊AC=12,所以AB=18,AD=DB=9, EB=DB-DE=3, CB=AB-AC=3, AD:CB=3:1
1、因为2DB=AB AC=AB-CB 3AC=2AB,所以4DB=3(2DB-CB)因桥做为CB=2EB,EB=DB-DE所以4DB=3(2DB-2DB+2DE)所以纯谨4DB=6DE=36所以AB=2DB=18
2、AD=DB=9,CB=敏裤衡2EB=2(DB-DE)=6所以AD:CB=3:2