神马作文网利润为：P=(x-12)y=(x-12)(-10x+200)=-10(x-12)(x-20)=-10[ x^2-32x+
(x+12)(x-2)+(x+7)(x+8)-(x+5)(x-10),其中x=2
1x+2x+3x+4x+5x+6x+7x+8x+9x+10x+11x+12x+13x+14x+15x=550
X/15 + X/12 + X/10 = 1365,求X,
已知实数x,y满足|x|+x+y=10、x+|y|-y=12,则x+y的值?
y=(x-1)(x-2)(x-3)(x-4)(x-5)(x-6)(x-7)(x-8)(x-9)(x-10)的导数在x=1
解分式方程(5-2x)/(x^2-x-12)=5x/(x^2+x-6)+(10-7x)/(x^2-6x+8)得
解方程x²+x-6分之5x+x²-x-12分之2x-5=x²-6x+8分之7x-10
解方程.（5x/x²+x-6）+（2x-5/x²-x-12）=7x-10/x²-6x+8
已知集合P={x|x^2-3x-10
x/2+x/8+x/12+x/20=1
解方程组:(x+3)(y-2)=(x-3)(y+10),(x+1)(y+3)=(x-2)(y+12)
已知x^2+y^2-10x-12y+61=0,求x/y-y/x的值