若|X-3|+|Y+15|=0,则3X+2Y=?

若2x-3y+4=0则x（x*x-1)+x(5-x*x)-6y+7 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2x=3y,则(x*x+y*y)/x*x=? 若x:y=3则x:(x+y)= 若(x-y)/(x+y)=3 则(x+2y)/(6x-7y)等于 若y=x(x-1)(x-2)(x-3),则y′（0）= 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,y满足|x-y+1|+(x+y+3)^2=0则x^2-y^2= 若x+y=4 4x+3y=15则 x-y=? 若5X-8Y=0,则X+3Y/X-3Y= 若|x|=2,|y|=3,且y/2+x《0则x+y 若|x+y-3|+(x-y-5)^2=0,则x)^2-y^2= 若[x-y+3]+|2x+y|=0,则x+y=? 若3x-2y=0,则X+y/x-y等于多少? （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