已知实数a,b分别满足a2-6a+4=0,b2-6b+4=0,且a≠b,则ba+ab的值是( )
治理黄河的根本措施是( )
1−310 =____
14+15 =____
14−15 =____
38+14 =____
56−13 =____
23−29 =____