5x-5-3+3y+7-7y=12-27+3x5y-5-3+3y+7-7y=100的答案

1.5（x+y）+3（x-y）=27（x+y）-3（x-y）=-62.x-y/7 - x+y/10 =1/22(x-y)-5(x+y)=3所谓细节决定成败, 2(x-2y)²-7(x-2y)³+3(2y-x)²+(2y-x)³合并同类项 这个式子2（x-2y)²-7（x-2y)³+3(2y-x)²-(2y-x)³=2（x-2y)²-7（x-2y)³+3(x-2y)²+(x-2y)³=5(x-2y)²-6(x-2y)³=(x-2y)²(5-6x+12y) 5(x-y)³-3（x-y）²+7(x-y)-5(x-y)³+（x-y）²-5（x-y）,其中,x-y=1/3.5(x-y)³-3（x-y）²+7(x-y)-5(x-y)³+（x-y）²-5（x-y）,其中,x-y=1/3先化简,再求值； {2x+y/3-2y=0 2(2x+y)-5=7y (3x+2y)(4x-5y)-12(x+y)(x-y)+7xy,其中x=2011,y=-1, x+y=1 5x-2y=8 3x-y=7 2x-y=3x表示y和用y表示x 3x+5y-(x+y)=6 2(x+y)-3x=-7 3(x+y)-4(x-y)=11,2(x-y)+5(x+y)=27 (3x-4y)(5x-4y)-(7x-8y)(6y-5x) 化简:3(x-y)²-7(x-y)+ 2(x-y)²+5(x-y) 把(x-y)看作一个整体,化解:5(x-y)+2(x-y)-4(x-y)= 3(x-y)把(x-y)看作一个整体,化解:5(x-y)+2(x-y)-4(x-y)=3(x-y)²-4(x-y)+7(x-y)-6(x-y)²= 计算(x^8-x^7y+x^5y^3-x^4y^4+x^3y^5-x^y^7+y^8)(x^2+xy+y^2) （x+y-5)*（x+y-5)+（x-y+3)=0 x*x-y*y Y=x+3 7x+5y=9 y-x=3 7x+5y=-9 y=x+3 7x+5y=9 {x+y=5{3x-7y=11 3x+5y=114x-y=7