(1) 过D作DE⊥AB交AB于E
∵AD是∠BAC的角平分线
∴∠CAD=∠EAD
∵DE⊥AB,∠C=90°
∴∠ACD=∠AED
∴∠ADC=∠ADE
AD为△ACD与△AED公共边
△ACD≌△AED
DE=DC=BC-BD=3
即点D到AB的距离为3
(2)点D到AB的距离是6即DE为6
由(1)得:BD:DC=3:2
BD:DE=3:2
BD"6=3:2
BD=9
BC=BD+CD
=BD+DE
=9+6=15
(1) 过D作DE⊥AB交AB于E
∵AD是∠BAC的角平分线
∴∠CAD=∠EAD
∵DE⊥AB,∠C=90°
∴∠ACD=∠AED
∴∠ADC=∠ADE
AD为△ACD与△AED公共边
△ACD≌△AED
DE=DC=BC-BD=3
即点D到AB的距离为3
(2)点D到AB的距离是6即DE为6
由(1)得:BD:DC=3:2
BD:DE=3:2
BD"6=3:2
BD=9
BC=BD+CD
=BD+DE
=9+6=15