4(3x-2y) 2(2y-3x),其中3x-2y=4,其中3x-2y=4-搜答案-智慧作业帮

写清楚点点比如说前面是X/X还是X/(X-Y)打上括号分段这样才能清楚的做

由(1)得3x+3y+2x-2y=365x+y=36(3)由(2)得4x+4y-3x+3y=-20x+7y=-20(4)(3)×7-(4)得34x=272∴x=8把x=8代入(3)得y=-4∴x=8y

{(x+y)/2+(x-y)/3=63(x+y)+2(x-y)=36(1)4(x+y)-3(x-y)=-20(2)由（1）*3+(2)*2得9(x+y)+6(x-y)+8(x+y)-6(x-y)=36

(x-3y)(y+2x)-(4y-3x)(3x+4y)=2x^2-3y^2-5xy+9x^2-16y^2=11x^2-5xy-19y^2

(2x+y)(2x-3y)+x(2y+y)=(2y+y)(2x-3y+x)=(2y+y)(3x-3y)=3(2y+y)(x-y)2a(x-y)-4b(x-y)=2(x-y)(a-2b)

化简得：-x+7y=11①7x+3y=27②①式×7得：-7x+49y=77③②+③得：52y=104∴y=2代入①得：x=3∴x=3,y=2再问：亲，是代入法哦！再答：代入法①式得3x+3y-4x+

（x+2)(x+3)=x²+5x+6(x-4)(x+1)=x²-3x-4(y+4)(y-2)=y²+2y-8(y-5)(y-3)=y²-8y+15x²

第二个方程是不是写错了2/（x+y）+3/（x-y）=6是这样吗

(x-3y)(x+y)-(x-2y)(x+2y)-(x-y)平方=x²-2xy-3y²-x²+4y²-x²+2xy-y²=(x²-

16(x+y)^8/9(x-y)^8=16/9*[(x+y)/(x-y)]^8哪个好理解用哪个.再问：有过程没。。。再答：这个过程其实没什么好研究的。。。[3(x-y)^2(x+y)^-2/4(x+y

原式=(2x²+8xy-3xy-12y²)-(3x²-6xy+xy-2y²)=2x²+8xy-3xy-12y²-3x²+6xy-x

=(x-y)[(3x+y)-(2x+3y)]*(x-y)=(x-y)*(x-y)(3x+y-2x-3y)=(x-y)(x-y)(x-2y)到底是化简,还是?=(x*x-2xy+y*y)(x-2y)=x

(2x-y)(2x+y)-2(3x-4y)(4y+3x)=4x²-y²-2(9x²-16y²)=4x²-y²-18x²+32y&s

解题思路：根据题意，由整式的运算的知识整理，分析可以求得解题过程：

解代数式得：-3x的平方y-2y的三次方因为1/2的平方=-1/2的平方,所以结果仍正确给分吧!嘿嘿!

3(x+y)-4(x-y)=4(x+y)/2+(x-y)/6=1令a=x+y,b=x-y3a-4b=4(1)a/2+b/6=1则3a+b=6(2)(2)-(1)5b=2b=2/5a=(6-b)/3=2

1.（（y+2x)(-2x+y)+4(x+2y)^2)/3y=(y^2-4x^2+4x^2+16xy+16y^2)/3y=(17y^2+16xy)/3y=17y/3+16x/32.（2(x-y)^3-

用提取公因式法,提取（x+3y)原式=（x+3y)[(3x-4y)-(x-2y)]=(x+3y)(2x-2y)=2(x+3y)(x-y)

(x+3y-4)(2x-y)

原式等于2x^2-xy+6xy-3y^2-8x+4y=2x^2+5xy-3y^2-8x+4y

我把方法告诉你,最后的答案你自己做吧,很容易.(x+y)(x+2y)(x+3y)(x+4y)=-40(x+y)（x+4y）(x+2y)(x+3y）=-40(x^2+5yx+44)(x^2+5yx+66