36-4(K-8)K=036-4K方+32K=0K方-8K-9=0(K+1)(K-9)=0 K=-1或9K=-1时 Y=-9X方-6X-1=-(3X+1)方 (-1/3,0)K=9时 Y=X方-6X+9=(X-3)方 (3,0)
