3x-2y=11,4x+3y=9如题

3x-2y=11,4x+3y=9如题 3(x+y)-2(x-y)=11 4(x+y)+3(x-y)=9 4(x-y)-3(x-y)=9 5(x-y)+2(x-y)=11 初一数学题求(x+y)(2x-y)-(x+2y)(x-2y)的值,其中x=3,y=4如题 如题{(X,Y)|(X+2)2+|Y-3|=0,X,Y属于R}= 如题{(X,Y)|(X+2)²+|Y-3|=0,X,Y属于R}= 根据3（x+y)-2(x-y)=11,4(x+y)+3(x-y)=9可得出x+y= ,x-y= 3(x+y)-4(x-y)=11,2(x-y)+5(x+y)=27 5x-(1-11y)/8=5y-6x+2/9=3x+4y+7/6如题,财富值不够,请见谅 (x-y) (x-2y)+(x+2y) (x-3y)-2(x-3y) (x-4y)= 3(x+y）-2（x-y）=11 4（x+y)+3（x-y）=9 接二元一次4(x+y)-3(x-y)=9;5(x-y)+2(x+y)=11 求y=4x^2+9/x^3(x>0)的最小值如题 已知x^2+y^2=5 xy=2 计算:(1) (x+y)^2 (2) x-y (3) x^4+y^4如题 已知：关于x,y的方程组{2x+y=-a+4,x+2y=3-a ,则x-y的值为?如题 若实数x,y满足（x+2y-2)(3x+2y+2)+2(x2+4)=0,求x+y的值.如题,请详细. (1)7x+3y=18 2x+3y=13 (2)5x+2y=7 2x+y=1 (3)3x+4y=5 4x+5y=6如题 解方程x+2y-9=0 3x-y+1=0如题