1数学题.
已知-m+2n=5,那么5(m-2n)^2+6n-3m-60的值为( )
A.80 B.10 C.20 D.40
需要详细解答
参考答案:A 80
5(m-2n)^2+6n-3m-60
=5(-5)^2+3*5-60
=5*25+15-60
=125+15-60
=80
已知-m+2n=5,那么5(m-2n)^2+6n-3m-60的值为( )
A.80 B.10 C.20 D.40
需要详细解答
参考答案:A 80
5(m-2n)^2+6n-3m-60
=5(-5)^2+3*5-60
=5*25+15-60
=125+15-60
=80