1）过点D作DH⊥AB交AB于H∵DH⊥AP∴DH=AD·sin30°=6×1/2=3∴y=S△APD=（DH·AP）/2∵AP=AB-BP=10-x∴y=3(10-x)/20＜x＜102）能若△AP1D∽△ABC则AB：AC=AP1：AD∴AP1=（6×10）/8=15/2若△AP2D∽△ACB则AB：AC=AD...
y=(10-x)*3=30-3x定义域:x大于等于0且小于10
1）过点D作DH⊥AB交AB于H∵DH⊥AP∴DH=AD·sin30°=6×1/2=3∴y=S△APD=（DH·AP）/2∵AP=AB-BP=10-x∴y=3(10-x)/20＜x＜102）能若△AP1D∽△ABC则AB：AC=AP1：AD∴AP1=（6×10）/8=15/2若△AP2D∽△ACB则AB：AC=AD...
y=(10-x)*3=30-3x定义域:x大于等于0且小于10
