x+4y=a 3x-2y=3a
设A={(x,y)}|3x+2y|.
已知集合A={(x,y)| (y-3)/ (x-1)=2,x,y∈R},B={(x,y)| 4x+ay=16,x,y∈
(2x+y)(2x-3y)+x(2y+y) 2a(x-y)-4b(x-y)
(1/2)已知实数x,y,a满足:根号(x+y-8)+根号(8-x-y)=根号(3x-y-a)+根号(x-2y+a+3)
x²(x+y)(y-x)-xy(x+y)(x-y) 已知a+b=4,ab=-2,求多项式3a²b+3
已知实数x、y、a满足:x+y-8+8-x-y=3x-y-a+x-2y+a+3
x y a满足根号下x+y-8+根号下8-x-y=根号下3x-y-a+根号下x-2y+a+3
已知方程组{x-2y=4+a 2x+3y=4a 满足x>0,y
3a(x+y)-2b(x+y)=(x+y)(?)
x+4y=a 3x-2y=3a
已知集合A={(x,y)|(y-3)/(x-2)=a+1}B={(x,y)|(a^2-1)x+(a-1)y=15},当a
已知3x+2y=a,2x+3y=b,则(x+y)(x-y)=?