问题
选择题
若|m-3|+(n+2)2=0,则m+2n的值为( )
A.-4
B.-1
C.0
D.4
答案
∵|m-3|+(n+2)2=0,
∴m-3=0且n+2=0,
∴m=3,n=-2.
则m+2n=3+2×(-2)=-1.
故选B.
若|m-3|+(n+2)2=0,则m+2n的值为( )
A.-4
B.-1
C.0
D.4
∵|m-3|+(n+2)2=0,
∴m-3=0且n+2=0,
∴m=3,n=-2.
则m+2n=3+2×(-2)=-1.
故选B.