问题 解答题

化简:

(1)5x-(3x-2y);

(2)7x-[-2x-(8x-1)].

答案

(1)5x-(3x-2y);

=5x-3x+2y

=2x+2y;

(2)7x-[-2x-(8x-1)]

=7x-[-2x-8x+1]

=7x+2x+8x-1

=17x-1.

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