数学:把原式去括号得:-3x-3y-5xy => -3(x+y)-5xy ,把x+y=6,xy=-4带入,得-3*6-5*(-4)=2,答案是2
英语:1.the bed 2.Something wrong is with 3.have light diet breakfast
4.eat a square meal 5.drive to,early
数学:把原式去括号得:-3x-3y-5xy => -3(x+y)-5xy ,把x+y=6,xy=-4带入,得-3*6-5*(-4)=2,答案是2
英语:1.the bed 2.Something wrong is with 3.have light diet breakfast
4.eat a square meal 5.drive to,early