∵（3xy+2）2+|7-x-y|=0，∴3xy+2＝07−x−y＝0，解得xy＝−23x+y＝7，∵原式=5xy+10y-（-5x-4xy+2y-3x）=5xy+10y-（-8x-4xy+2y）=5xy+10y+8x+4xy-2y=9xy+8（x+y）∴原式=9×（-23）+8×7=-6+56=50．...