如果-x+2y=5,则5(x-2y)²-3(x-2y)-60=
问题描述:
如果-x+2y=5,则5(x-2y)²-3(x-2y)-60=
答
由-x+2y=5 得:x-2y=-5
5(x-2y)²-3(x-2y)-60
=5(-5)²-3*(-5)-60
=125+15-60
=80