已知-x+2y=5,那么5(x一2y)∧2一3(x一2y)一60的值为( ) A已知-x+2y=5,那么5(x一2y)∧2一3(x一2y)一60的值为( ) A -17 B -7 C -3 D 7

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已知-x+2y=5,那么5(x一2y)∧2一3(x一2y)一60的值为( ) A已知-x+2y=5,那么5(x一2y)∧2一3(x一2y)一60的值为( ) A -17 B -7 C -3 D 7

已知-x+2y=5,那么5(x一2y)∧2一3(x一2y)一60的值为( ) A已知-x+2y=5,那么5(x一2y)∧2一3(x一2y)一60的值为( ) A -17 B -7 C -3 D 7
已知-x+2y=5,那么5(x一2y)∧2一3(x一2y)一60的值为( ) A
已知-x+2y=5,那么5(x一2y)∧2一3(x一2y)一60的值为( ) A -17 B -7 C -3 D 7

已知-x+2y=5,那么5(x一2y)∧2一3(x一2y)一60的值为( ) A已知-x+2y=5,那么5(x一2y)∧2一3(x一2y)一60的值为( ) A -17 B -7 C -3 D 7
-x+2y=5
∴x-2y=-5
5(x一2y)∧2一3(x一2y)一60
=5×(-5)^2-3×(-5)-60
=125+15-60
=80

把-x=5-2y代入

就是80