1ï¼å¨ç´è§ä¸è§å½¢AODä¸ï¼ç±å¾è¡å®çï¼å¾ï¼
AD^2=AO^2+OD^2=4^2+3^2=25
解å¾AD=5,
å 为AB为ç´å¾
æ以â ACB=90,
åâ Aä¸ºå ¬å ±è§
æ以â³AODâ½â³ACB
æ以AO/AC=AD/AB
å³4/AC=5/8,
解å¾AC=32/5
æ以CD=AC-AD=32/5-5=7/5
2)ç±â³AODâ½â³ACBï¼å¾ï¼
OD/CB=AD/AB
å³3/BC=5/8
解å¾BC=24/5