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解下列方程:(1)5(x%5)+2(x)=0;(2)4x+...

(1)去括号得:5x-25+2x-24=0,移项合并得:7x=49,解得:x=7;(2)去括号得:4x+3=2x-2+1,移项合并得:2x=-4,解得:x=-2;(3)方程整理得:0.7+3x?22=15?50x5,去分母得:7+15x-10=30-100x,移项合并得:115x=33,解得:x=33115;(4)去...

(1)把方程直接开平方得:x-5=±4,∴x 1 =-5-4=-9,x 2 =4-5=-1;(2)a=1,b=-4,c=1,∴x= -b± b 2 -4ac 2a = 4± 16-4 2 = 4± 2 3 2 =2± 3 ;(3)a=1,b=-4,c=5,∵△=b 2 -4ac=16-20=-4<0,∴次方程无解.(4)a=1,b=5,c=3,∴x= -b± b 2 -4...

2(x-5) 2 -(x-5)=0,(x-5)(2x-10-1)=0,解得:x 1 =5,x 2 = 11 2 .(2)原方程可化为:(x-8)(x+4)=0,解得:x 1 =8,x 2 =-4.(3)原方程可化为:x 2 +6x+9-2x-5=0,(x+2) 2 =0,解得:x=-2.(4)原方程可化为:2x 2 -6x+x-3...

(1)x(x+1)=0,x=0或x+1=0,∴x1=0,x2=-1;(2)(2x+11)(2x-11)=0,2x+11=0或2x-11=0,∴x1=-112,x2=112;(3)(2x+1)(3x-2)=0,2x+1=0或3x-2=0,∴x1=-12,x2=23;(4)(x-4+5-2x)(x-4-5+2x)=0,(1-x)(3x-9)=0,1-x=0或3x-9=...

①去括号得:x2-x-6-x2+7x-6=0,移项合并得:6x=12,解得:x=2;②去括号得:2x2+4x-30-2x2-13x+7≤4,移项合并得:-9x≤27,解得:x≥-3.

(1)方程开方得:2x-1=3或2x-1=-3,解得:x1=2,x2=-1;(2)分解因式得:(x-1)(x+4)=0,解得:x1=1,x2=-4;(3)方程变形得:(x+4)2-5(x+4)=0,分解因式得:(x+4)(x+4-5)=0,解得:x1=-4,x2=1;(4)方程变形得:x2+4x+4=6,即...

(1)logx+2(4x+5)-log4x+5(x2+4x+4)-1=0化为logx+2(4x+5)-2[logx+2(4x+5)]-1-1=0令t=logx+2(4x+5)上式化为:t?2t?1=0 即 t2?t?2=0 解得t=?1,t=2当logx+2(4x+5)=-1时解得x=-1或x=?94都不符合题意,舍去.当logx+2(4x+5)=2时...

(1)x2-4x+4=3,(x-2)2=3,x-2=±3,则x1=2+3,x2=2-3;(2)3(x-5)2+2(x-5)=0,(x-5)[3(x-5)+2]=0,x-5=0或3(x-5)+2=0,x1=5,x2=133.

(1)196x2-1=0,整理,得(14x+1)(14x-1)=0,令14x+1=0或14x-1=0,解,得x1=-114,x2=114.(2)4x2+12x+9=81整理,得x2+3x-18=0,即:(x+6)(x-3)=0令x+6=0或x-3=0,解,得x1=-6,x2=3.(3)x2-7x-1=0即:x=7±72+42=7±532,∴x1=7+532,...

(1)方程去括号得:x2-5=20,即x2=25,解得:x=±5;(2)这里a=2,b=-3,c=-6,∵△=(-3)2-4×2×(-6)=9+48=57,∴x=3±574;(3)分解因式得:(x-2)(2x+1)=0,可得x-2=0或2x+1=0,解得:x1=2,x2=-12;(4)开方得:x-2=2x+3或x-2=-(2x+3)...

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