问题:
若(2x-5y) 2=(2x+5y) 2+m,则代数式m为
A.-20xy
B.20xy
C.40xy
D.-40xy
若(2x-5y) 2=(2x+5y) 2+m,则代数式m为
A.-20xy
B.20xy
C.40xy
D.-40xy
A.-20xy
B.20xy
C.40xy
D.-40xy
参考答案: