解方程：x2-7x+6=0
原式可变为：
（x-6）（x-1）=0
解方程得x1=1，x2=6．
40. —Good evening. Huangshan Hotel.
—Good evening. ______________?
A．Do you still have a room for tonight
B．What would you like, please
C．Is there anything I can do for you
D．Who is that speaking, please
烟草订货按照烟草公司的有关规定，采取电话访销或（）的方式，订货数量、品种须经（）或（）管理人员审批。
______________?