化简:(1):4m-7n-2(m-2n).(2):-(x²-2xy-y²)+95x²-2xy-3y²).

问题描述:

化简:(1):4m-7n-2(m-2n).(2):-(x²-2xy-y²)+95x²-2xy-3y²).

题目应是 化简:(1):4m-7n-2(m-2n).(2):-(x²-2xy-y²)+(5x²-2xy-3y²).(1):4m-7n-2(m-2n)=4m-7n-2m+4n=2-3n(2):-(x²-2xy-y²)+(5x²-2xy-3y²)= -x²+2xy...