(10+50)*X+(46-2X)*100=1800怎么解仔细一点,题目是现有10元,50元,100元人民币共46张,共1800元,其中10元与50元张数相等,那么50元的人民币共有多少张?

10x+2x*[(50-x)/2]+5x[(50-x)/2]=240 (x^2-x)^2-18(x^2-x)+72(x+1)(x+2)-x-10 (x+12)(x-2)+(x+7)(x+8)-(x+5)(x-10),其中x=2 (x-1)/(x+3x+2)+6/(2+x-x)-(10-x)/(4-x) 因式分解(x+1)(x+2)-x-10(x²-x)²-18(x²-x)+72 =(x^2-5x)^2+10(x^2-5x)+24 =x^4-10x^3+25x^2+10x^2-50x+24 这是怎么转化的(X-1)(X-2)(X-3)(X-4) =(X-1)(X-4) (X-2)(X-3)=（x^2-5x+4)(x^2-5x+6)=(x^2-5x)^2+10(x^2-5x)+24=x^4-10x^3+25x^2+10x^2-50x+24=x^4-10x^3+35x^2-50x+24 2x+8-10x+50=5x-10 50*2X=X*（50-X）*10 =（x^2-5x+4)(x^2-5x+6) =(x^2-5x)^2+10(x^2-5x)+24 是怎么转化的(X-1)(X-2)(X-3)(X-4) =(X-1)(X-4) (X-2)(X-3)=（x^2-5x+4)(x^2-5x+6)=(x^2-5x)^2+10(x^2-5x)+24=x^4-10x^3+25x^2+10x^2-50x+24=x^4-10x^3+35x^2-50x+24不好意思我弄错了，是=（x^2-5 化简：2x^2-50/x^2-10x+25 解方程(x/x(x+2))+(x/(x+2)(x+4))+.+x/(x+8)(x+10)=1 X+X+X+(X-1)+(X-2)+(X-3)+(X-4)=10(X-3)+(X-4) x^2+10x( )=(x+ )^2 x^2-10x=2-x (X-2)(X+3)+3x+10 2x×x=10,求x 0.3x+7x-0.25x=21.15 x+7=2x+3 1.2x+1=0.01x+三分之五 4x-26=3x+4 6x+2=5x+110.3x+7x-0.25x=21.15x+7=2x+31.2x+1=0.01x+三分之五4x-26=3x+46x+2=5x+114(x+1)=x+10 x+2x×10=10x+2x+36