Question

若a+b=-1,ab=4,则(4a-5b-3ab)-(3a-6b+ab)的值为____.

Answer

-17

【解析】

先去括号,再合并同类项,把a+b和ab的值代入求出即可.

解:.a+b=-1,ab=4,

(4a-5b-3ab)-(3a-6b+ab)

=4a-5b-3ab-3a+6b-ab

=a+b-4ab

=-1-44

=-17,

故答案为:-17.