问题 解答题
先去括号,再合并同类项:
(1)-6m+(3m-4)-(5m-7);  
(2)2(3a2+2a-1)-
1
2
(a2+8a-6)
答案

(1)原式=-6m+3m-4-5m+7

=-8m+3;

(2)原式=6a2+4a-2-

1
2
a2-4a+3

=5.5a2+1.

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