7x-3y+1=0,4x-5y=-17怎么解

初二上学期方程题 4x+y=5 5x+4y=63x-2y=1 2x+3y=13x-2y=7 7x+5y=32x+3y=17 2x-y=-4x+5y=6 2x+y=23x-6y=4 3x+2y=52x+y=73x-4y=53x+y=1x-2y=-1x+y=42x+3y=92x-3y=74x+5y=3x+y=20004x+6y=90003x+5y=113x-2y=42x+3y=215x-2y=5x+y=54x+3y=182x+3y=16x+4y=132x+3y=40x 若2x-3y+4=0则x（x*x-1)+x(5-x*x)-6y+7 已知(3x+1)(3x-3)-3x+2)^2=-7,(y+7)(y-7)-y(y-7)=0,求8y^2-5y(-y+3x)+4y(-4y-5/2x)的值 （x+y-5)*（x+y-5)+（x-y+3)=0 x*x-y*y 已知:3x-5y=0,求x/y,x-y/y,x-y/x [(x+2y)²-（x+y)(3x-y)-5y²]÷(2x),其中x,y满足x²+4x+y²-y+17/4=0已知、x+y=6且xy=4(1)x²+y² (2)（x-y）² (3)x{四次方}+y{四次方}第一题没错 书上就这样写的！ 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= 代入法解方程组(1)2y-8=-x (2)x-y=5 (3)2x+3y=7 (4)y=x+1 4x+3y=10 4x+3y=7 3x-6y=0 3x+4y=11 (5)y=x+1 3x+4y=11(6) x-5y=03x+2y=17记得详细一点.. {x+y=1 ,xy=-6{x(2x-3)=0,y=x²-1{(3x+4y-3)(3x+4y+3)=0,3x+2y=5{(x-y+2)(x+y)=0,x²+y²=8{(x+y)((x+y-1)=0,(x-y)(x-y-1)=0 帮忙解一些方程组(1)3x-2y=6 2x+3y=17 (2)5x+6y=15.2 3x-2y=-0.4(3)2(x+y)-3y=7 4(x-9)=3(y-2)(4)3(x+y)-4(x-y)=4 x+y/2+x-y/6=1 化简[(3x+4y)^2-(2x+y)(2x-y)+(-x+y)(5x-y)]除以-2y,其中x=-1,y=1 3x+4y-5=0 x^2+y^2=1求x.y 1.{5x=7y-1 5x=17-14y 2.{x=16-4y y=34-4x 3.{x+y=7 x:5=y:2 4.{x+2y=1 x-4y=-22 5.{3x=y+1/2 3x=y/4 1.{5x=7y-1 5x=17-14y 2.{x=16-4y y=34-4x 3.{x+y=7 x:5=y:2 4.{x+2y=1 x-4y=-22 5.{3x=y+1/2 3x=y/4 求解(1){2x-y=9 3x+y=7 (2)｛4x-3y=5.6 5x+3y=7.4 (3)｛2x+3y+19=0 x+5y-1=0(4)｛x+y/2+x-y=1 4（x+y)-5(x-y)=2 请解答方程组：（39）2x+y=5 (40)x+y=7 (41)2x+3y=12 (42)2x+y=3ax+3y=7 2x-y=8 3x+4y=17 3x-5y=11(43)3x+y=82 (44)3(x-1)=y+5 45 x/4+y/3=7 (46)x+y/3 +x-y/2=610x-11y=87 5(y-1)=3(x+5) 2/3x+y/2=14 3(x+y-)2(x-y)=28 解下列方程组：{x(2x-3)=0,y=x²-1{(3x+4y-3)(3x+4y+3)=0,3x+2y=5{(x-y+2)(x+y)=0,x²+y²=8{(x+y)((x+y-1)=0,(x-y)(x-y-1)=0 已知7x+5y/2y-x=3/2,且x≠0,求X/x-4y