x+y=10 4x+2y
已知2x-y=10,求[(x²+y²)-(x-y)²+2y(x-y)]/4y
(4x-2y-z)-{5x[8y-2y-(x+y)]-x+(3y-10z)]=? kuai
已知2x-y=10,求式子[(x^2+y^2)-(x-y)^2+2y(x-y)]/4y (4xy-2y²)/4
已知:4x^2+y^2-4x-6y+10=0,求y/x-x/y的值
解方程组 10(x-y)=3(x+y)+15 6(x+y)=4(2x-y)+16
{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
3(x+y)-4(x-y)=11,2(x-y)+5(x+y)=27
4(x+y)-3(x-y)=-20,2/x+y+3/x-y=6
已知4x=9y求(1)x+y/y (2)y-x/2x
(x+y)(x+2y)(x+3y)(x+4y)=-40