(1)x(x-3)+2x-6=0.分解因式得:x(x-3)+2(x-3)=0,即(x+2)(x-3)=0,可得x+2=0或x-3=0,解得:x1=-2,x2=3;(2)x2-x=5x+1,移项得:x2-6x=1,配方得:x2-6x+9=10,即(x-3)2=10,可得:x-3=± 10 ,∴x1=3+ 10 ,x2=3- 10 .