x÷10-2x÷10=60÷20

(x+1-1/1-x)÷(x-x²/x-1)=[(x+1)+1/(x-1)]×[-(x-1)/x(x-1)]=(x²-1+1)/(x-1)×(-1/x)=-x/(x-1)(x-4/

（x+2/x²-2x-x-1/x²-4x+4）÷x-4/x={(x+2)(x-2)/[x(x-2)²]-x(x-1)/[x(x-2)²]}·x/(x-4)={(

(x/x(x+2))+(x/(x+2)(x+4))+.+x/(x+8)(x+10)=(x/2)*(2/x(x+2))+(2/(x+2)(x+4))+.+2/(x+8)(x+10)=(x/2)*[1/x

(10-√2X×2X-25)÷2=X10-√(4x^2-25)=2x√(4x^2-25)=10-2x4x^2-25=100-40x+4x^240x=125x=25/8

注意：本题x=2时题目没意义,应该舍去（这是很多学生错误所在）这里x只能取根号2-1  

(1)1+0.4x=0.2(x+10)（2）x÷2=x+2001+0.4x=0.2x+2-200=x/20.2x=1-400=xx=5x=-400

(120-X)÷120+(120-2x)÷50=x÷10(120-x)/12+(120-2x)/5=x5(120-x)+12(120-2x)=60x600-5x+1440-24x=60x89x=204

原式=2x(x-2)/(x+2)×x(x+2)/(x-2)²×3(x-2)/x=6x当x=√3/2时原式=3√3

(x^2+7x+10)/(x^2+6x+5)×(x^3+1)/(x^2+4x+4)÷(x^2-x+1)/(x+2)=(x+2)(x+5)/(x+1)(x+5)*(x+1)(x^2-x+1)/(x+2)

先一个一个的展开括号项,再同项合并就行了啊[x(x-y)-y(x-y)+(x+y)(x-y)]÷2x=[xx-xy-(xy-yy)+x(x-y)+y(x-y)]÷2x=[xx-xy-xy+yy+xx-

x^3-2x^2+4x/x^2-4x+4÷x^2-2x+4/x-2=x(x²-2x+4)/(x-2)²÷(x-2)/(x²-2x+4)=x(x²-2x+4)/(

①(-x)^3·x·(-x)^4÷x^5=-x^4*(-x)^4÷x^5=x^8÷x^5=x^3②(x^3)^4+x^10·x^2+x·x^3·x^8=x^12+x^12+x^12=3x^12③(16

题目打错了,看看是下面这样吗?﹙x²－1﹚／﹙x²＋4x＋4﹚÷﹙x＋1﹚×﹙2x＋4﹚／﹙x－1﹚=[﹙x－1﹚﹙x＋1﹚／﹙x＋2﹚²]×[1／﹙x＋1﹚]×[2﹙x

4.316.73.572.5245.2再问：过程、再答：x+5.7=10移项x=10-5.7=4.3x-6.2=10.5移项x=10.5+6.2=16.73x=10.5x=10.5/3=3.5x÷7=

设这个数为X则：5X+0.5=505X=49.5X=9.9再答：3.32.8/(7+1)=4.14.设这个数是X45%X+3.6=12.6X=205.圆的周长为2πr=2*3.14*2=12.56则正

=x^2+10x-24+x^2+15x+56-x^2+5x+50=x^2+30x+82=4+60+82=146其实,不化简,直接代入=14*0+9*10+7*8=0+90+56=146也很简单

10x+160=240x+16=24x=24-16x=8

x(2-1/x)+x/(x^2-2x)÷(3-x)/(x^2-4)=x((2x-1)/x)+x/(x^2-2x)x(x^2-4)/(3-x)=(2x-1)+(x+2)/(3-x)=(7x-3-2x^2

(1)2+x/10=3/10x+1x/5=1x=5(2)3/25x+21/5-7/50x=41/5=1/50xx=10(3)未知数不见了(4)1.5x+165-1.1x=1700.4x=5x=12.5

130%x+x=4.61.3x+x=4.62.3x=4.6x=2x÷50%=10x=10乘2x=20x/9-x/15=16%x（1/9-1/15）=16/100x（5/45-3/45）=4/25x=4