（4x^2-9y^2)/(2x+3y)=多少

x/4+2等于x,x=多少.y/5等于y-3,Y=多少 9y=3x-(x-1),4(x+y)-(2x+4)=8y 9x+8y=-2,4x+5y=-11,y最后等于多少 已知4x=9y求(1)x+y/y (2)y-x/2x （4x^2-9y^2)/(2x+3y)=多少 {3(x+y)-4(x-y)=4 {x+y/2 + x-y/6=1 x+y/2+x-y/3=6,4(x+y)-3(x-y)=-20 {(x+y)/2+(x-y)/3=6 4(x+y)-3(x-y)=-20 4(x+y)-3(x-y)=-20,2/x+y+3/x-y=6 2 2x+5y=-1,4x+9y=-3,结果是多少? 3(x+y)-4(x-y)=11,2(x-y)+5(x+y)=27 (x+y)(x+2y)(x+3y)(x+4y)=-40