若(x+3)2+(2y-6)2=0,则x2+y2的值为?-3、3、-1/3、1/3括号以外的是平方

若2x-3y+4=0则x（x*x-1)+x(5-x*x)-6y+7 若(x-y)/(x+y)=3 则(x+2y)/(6x-7y)等于 若2x=3y,则(x*x+y*y)/x*x=? 若3x-5y=0,则x+y/x=（）,x-y/y=（）,2x-3y/2x+3y=( ) 若x-y不等于0,2x-3y=0,则分式(10x-11y)/(x-y)的值是（）?(10x-11y)/(x-y) =[(8x-8y)+(2x-3y)]/(x-y) =8为什么8X-8Y=8？(10x-11y)/(x-y)=[(8x-8y)+(2x-3y)]/(x-y)=8+(2x-3y)]/(x-y)=8+0=8 若（3x+y+6)^2+|x+y+2|=0,则x= 若y=x(x-1)(x-2)(x-3),则y′（0）= 若x,y满足|x-y+1|+(x+y+3)^2=0则x^2-y^2= 若x,y满足|2x-y-3|+|3x+2y+1|=0,则x= y= 若线段x ,y 满足[2x-3y]*[3x+2y]=0 则x/y=? 若x^2+y^2-6x+8y+25=0 则y/x-x/y的值是 若5x+3y=3x+4y=x+2y+6,则x+y=___ 若x^2+2x+y^2-6y+10=0,则x-y 若|x+y-3|+(x-y-5)^2=0,则x)^2-y^2= 若x^2+y^2-10x+6y+34=0,则x+y=? 若x^2-y^2=6 x+y=3 则x-y=多少 若|x|=2,|y|=3,且y/2+x《0则x+y 若2x+2y=6x-3y,则x比y=