问题
填空题
若-x+2y=5,则5(x-2y)2-3x+6y-60=______.
答案
∵-x+2y=5,
∴x-2y=-5
∴5(x-2y)2-3x+6y-60
=5(x-2y)2-3(x-2y)-60
=5×(-5)2-3×(-5)-60
=125+15-60
=80.
故答案为80.
若-x+2y=5,则5(x-2y)2-3x+6y-60=______.
∵-x+2y=5,
∴x-2y=-5
∴5(x-2y)2-3x+6y-60
=5(x-2y)2-3(x-2y)-60
=5×(-5)2-3×(-5)-60
=125+15-60
=80.
故答案为80.