12 [2 5*0.75 [1 2 x]*3]*0.3=98

x：12=23：4，      4x=12×23，    4x÷4=13÷4，  

X-25%X=300.75X=30X=30/0.75X=402X+30%X=9.22.3X=9.2X=9.2/2.3X=475%X-45%X=120.3X=12X=12/0.3X=40X+120%X=

用“两内项之积等于两外项之积”.1、12X=322,X=161/7.2、56X=15*13,X=195/56.3、54X=34*2,X=34/27.4、25X=81*0.75,X=2.43.再问：请把

1.x-25%x=30X=30/0.75=402.2x+30%x=9.2x=9.2/2.3=43.75%x-45%x=12x=12/0.3=404.x+120%x=33x=33/2.2=15再问：能讲

解(1)x-0.75x=120.25x=121/4x=12x=12×4x=48(2)2.8x+x=7.63.8x=7.6x=7.6÷3.8x=2(3)2.36x+2.64x=185x=18x=18÷5

主要是考察因式分解这方面的技能啊![(2x²-5x+2)/(6x²+13x+6)]*[(6x²-5x-6)/(6x²-17x+10)]*[(12x²+

x+25%x=25001.25x=2500x=2000x-12%x=4.40.88x=4.4x=545%x+15%x=360.6x=36x=60120%x-x=560.2x=56x=28048%x-1

应该是-2x²,不是-3x²3x²-x=1原式=9x^4-3x³+15x³-5x²+3x²-7x+2001=3x²(3x

7x-12%=5.87x=2.8+1.27x=4x=4/725+75%x=32.50.75x=32.5-250.75x=7.5x=1080%x-46%x=10.20.34x=10.2x=10.2÷0.

5x+2x=33.6,7x=33.6;x=4.8;7x-4x=0.75,3x=3/4;x=1/4;2x+7x+2.1=12,9x=8.1;x=0.9;56x-32x-119=36124x=480;x=

25%x=200x=200/25%x=800x+35%x=540x(1+35%)=540x=540/1.35x=400x-0.78%x=8.822%x=8.8x=4048%x-12%x=3636%x=

4(x-3)^2=25(x-3)^2=25/4x-3=±5/2x1=1/2x2=11/5(x-1)(x+3)=12x²+2x-3-12=0x²+2x-15=0(x-3)(x+5)=

4X²-3X=0x(4x-3)=0x=0或x=3/44X²-25=0x²=25/4x=5/2或-5/29X²+12X+4=0(3x+2)²=0x1=x

20%x+[25*20%x]+12=50%x+20.2x+5x+12=0.5x+24,7x=-10x=-100/47

再答：最后一题打错了吧？再问：您真是个好人再问：在问你一题再答：嗯再问：再答：看不清再问：没错呀再问：问一下再问：缺勤人数怎么求再答：看不清你题再问：缺勤率再问：怎么求再问：各年级总人数怎么求再答：已

(X-7)(X+2)

3.5X—1.5X=10.82x=10.8x=5.42.36X+2.64X=185x=18x=3.6X—0.75x=120.25x=12x=482.8X+X=7.63.8x=7.6x=2

6[(3^x)²-2+(3^-x)²]-25(3^x-3^-x)+24=0[2(3^x-3^-x)-3][3(3^x-3^-x)-8]=02*3^x-3-2*3^-x=03*3^x

=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

答：结论是无解的设1和4中间的正方形边长为x则左边中间的正方形边长为x+1左下角边长为x+1+x=2x+1所以：右下角正方形边长2x+1+x-4=3x-3所以：最大的正方形底部边长=2x+1+3x-3