化简3(x²y+xy)-4(x²y-xy)-5x²y,

问题描述:

化简3(x²y+xy)-4(x²y-xy)-5x²y,

5xy-8x*xy

3(x²y+xy)-4(x²y-xy)-5x²y
=3x²y+3xy-4x²y+4xy-5x²y
=-6x²y+7xy