6y=2(1+y)-3(y+3)和2(x+0.5)-3(x-0.4)=5.6

(2x-2y)/3-(x-y)=-1和6(x+y)-4(2x-y)=16 解方程组3(x+y)-4(x-y)=4和(x+y)/2+(x-y)/6=1kkkkkkkk (x-2y)(x+y)-2x(-2x-3y)+6x(-x-y),其中x=-1,y=2要讲解和答题 2(x+y)-3(x-y)=1 6(x+y)+(x-y)=51 {3(x+y)-4(x-y)=4 {x+y/2 + x-y/6=1 已知：2x+y=6,x-3y=1 求7y(x-3y)(x-3y)-2(3y-x)(3y-x) x+y=1 5x-2y=8 3x-y=7 2x-y=3x表示y和用y表示x (x+y)(x-y)+(x-y)^2-(6x^2×y÷2y-2xy^2÷2y)其中x=-3,y=1/3 常微分方程的通解dy/dx=(x-y+1)/(x+y-3)y^4=2y^n+y=0y''+6y'+9y=e^(-3x)y''+y'-2y=4e^(2x) 【2(x-y)^3-8(x-y)^2(x+y)+6y(x-y)^2】/2(x-y)^2= 已知方程组2X+Y=6和X-3Y=1不解方程组,求7Y(X-3Y)^2-(3Y-X)^3 已知X,Y,满足(X+3Y)(X-3Y)=-10(Y^2-6/5)和2X(Y-1)+4(1/2X-1)=0 （X+Y)^2 X^2Y+XY^2注：*/* 是分数 2x+4y=3 -3x-2y=1 ..求x和y 解方程组,(x+y)^2-3(x+y)=0和x-y=1 已知X和Y满足3X+4Y=2,X-Y-1/7 解二元一次方程组：3(x+y)-4(x-y)=4,x+y/2+x-y/6+1x+y/2+x-y/6+1=1 若2/x-1/y=3,求[y/x-y/x-y(x-y/x-x+y)]/x-2y/x的值 (3x-y)^2+(3x+y)(3x-y),x=1,y=-2