Question

已知x+y-3是64的立方根,x-y-2是25的平方根,求2x-y的值

Answer 1

x+y-3=4

x-y-2=±5

x-y-2=5时

x=7,y=0

2x-y=14

x-y-2=-5时

x=2,y=5

2x-y=-1