Câu hỏi của Tô Thu Huyền

Question

Tìm x,biết:a./2x + 1/ = $\frac{3}{5}$                                            b. $\frac{x+3}{4}$ = $\frac{-7}{2}$ c. ($\frac{7}{2}$ - 2x ) . $\frac{4}{3}$ = $\frac{22}{3}$             ...

Nguyễn Võ Hà Trang · Accepted Answer

a,$\left|2x+1\right|=\frac{3}{5}$$2x+1=+-\frac{3}{5}$$\left[\begin{array}{nghiempt}2x+1=\frac{3}{5}\Rightarrow x=-\frac{1}{5}\2x+1=-\frac{3}{5}\Rightarrow x=-\frac{4}{5}\end{array}\right.$Vậy $x\in\left\{-\frac{1}{5};-\frac{4}{5}\right\}$$\frac{x+3}{4}=-\frac{7}{2}$$\Leftrightarrow2\left(x+3\right)=4.\left(-7\right)$$2\left(x+3\right)=-28$$\left(x+3\right)=28:2$$x+3=14\$$\Rightarrow x=14-3$$x=11$$\left(\frac{7}{2}-2x\right).\frac{4}{3}=\frac{22}{3}$$\left(\frac{7}{2}-2x\right)=\frac{22}{3}:\frac{4}{3}$$\left(\frac{7}{2}-2x\right)=\frac{11}{2}$$2x=\frac{7}{2}-\frac{11}{2}$$2x=2$$x=1$$\left(\frac{7}{3}+\frac{7}{2}\right).x=-\frac{25}{6}+\frac{22}{7}$$\frac{35}{6}.x=-\frac{43}{42}$$x=-\frac{43}{42}:\frac{35}{6}$$x=-\frac{43}{245}$ Câu trả lời: a,$\left|2x+1\right|=\frac{3}{5}$$2x+1=+-\frac{3}{5}$$\left[\begin{array}{nghiempt}2x+1=\frac{3}{5}\Rightarrow x=-\frac{1}{5}\2x+1=-\frac{3}{5}\Rightarrow x=-\frac{4}{5}\end{array}\right.$Vậy $x\in\left\{-\frac{1}{5};-\frac{4}{5}\right\}$$\frac{x+3}{4}=-\frac{7}{2}$$\Leftrightarrow2\left(x+3\right)=4.\left(-7\right)$$2\left(x+3\right)=-28$$\left(x+3\right)=28:2$$x+3=14\$$\Rightarrow x=14-3$$x=11$$\left(\frac{7}{2}-2x\right).\frac{4}{3}=\frac{22}{3}$$\left(\frac{7}{2}-2x\right)=\frac{22}{3}:\frac{4}{3}$$\left(\frac{7}{2}-2x\right)=\frac{11}{2}$$2x=\frac{7}{2}-\frac{11}{2}$$2x=2$$x=1$$\left(\frac{7}{3}+\frac{7}{2}\right).x=-\frac{25}{6}+\frac{22}{7}$$\frac{35}{6}.x=-\frac{43}{42}$$x=-\frac{43}{42}:\frac{35}{6}$$x=-\frac{43}{245}$

Phương An · Answer

a.$\left|2x+1\right|=\frac{3}{5}$$2x+1=\pm\frac{3}{5}$TH1:$2x+1=\frac{3}{5}$$2x=\frac{3}{5}-1$$2x=\frac{3-5}{5}$$2x=-\frac{2}{5}$$x=-\frac{2}{5}\div2$$x=-\frac{2}{5}\times\frac{1}{2}$$x=-\frac{1}{5}$TH2:$2x+1=-\frac{3}{5}$$2x=-\frac{3}{5}-1$$2x=\frac{-3-5}{5}$$2x=-\frac{8}{5}$$x=-\frac{8}{5}\div2$$x=-\frac{8}{5}\times\frac{1}{2}$$x=-\frac{4}{5}$Vậy x = -1/5 hoặc x = -4/5.b.$\frac{x+3}{4}=-\frac{7}{2}$$x+3=-\frac{7}{2}\times4$$x+3=-14$$x=-14-3$$x=-17$c.$\left(\frac{7}{2}-2x\right)\times\frac{4}{3}=\frac{22}{3}$$\left(\frac{7}{2}-2x\right)=\frac{22}{3}\div\frac{4}{3}$$\left(\frac{7}{2}-2x\right)=\frac{22}{3}\times\frac{3}{4}$$\frac{7}{2}-2x=\frac{11}{2}$$2x=\frac{7}{2}-\frac{11}{2}$$2x=-\frac{4}{2}$$x=-2\div2$$x=-1$d.$\left(\frac{7}{3}+\frac{7}{2}\right)\times x=\frac{-25}{6}+\frac{22}{7}$$\left(\frac{14+21}{6}\right)\times x=-\frac{25}{6}+\frac{22}{7}$$\frac{35}{6}\times x=-\frac{25}{6}+\frac{22}{7}$$x=\left(-\frac{25}{6}+\frac{22}{7}\right)\div\frac{35}{6}$$x=\left(-\frac{25}{6}+\frac{22}{7}\right)\times\frac{6}{35}$$x=-\frac{25}{6}\times\frac{6}{35}+\frac{22}{7}\times\frac{6}{35}$$x=-\frac{5}{7}+\frac{132}{245}$$x=-\frac{43}{245}$Câu trả lời: a.$\left|2x+1\right|=\frac{3}{5}$$2x+1=\pm\frac{3}{5}$TH1:$2x+1=\frac{3}{5}$$2x=\frac{3}{5}-1$$2x=\frac{3-5}{5}$$2x=-\frac{2}{5}$$x=-\frac{2}{5}\div2$$x=-\frac{2}{5}\times\frac{1}{2}$$x=-\frac{1}{5}$TH2:$2x+1=-\frac{3}{5}$$2x=-\frac{3}{5}-1$$2x=\frac{-3-5}{5}$$2x=-\frac{8}{5}$$x=-\frac{8}{5}\div2$$x=-\frac{8}{5}\times\frac{1}{2}$$x=-\frac{4}{5}$Vậy x = -1/5 hoặc x = -4/5.b.$\frac{x+3}{4}=-\frac{7}{2}$$x+3=-\frac{7}{2}\times4$$x+3=-14$$x=-14-3$$x=-17$c.$\left(\frac{7}{2}-2x\right)\times\frac{4}{3}=\frac{22}{3}$$\left(\frac{7}{2}-2x\right)=\frac{22}{3}\div\frac{4}{3}$$\left(\frac{7}{2}-2x\right)=\frac{22}{3}\times\frac{3}{4}$$\frac{7}{2}-2x=\frac{11}{2}$$2x=\frac{7}{2}-\frac{11}{2}$$2x=-\frac{4}{2}$$x=-2\div2$$x=-1$d.$\left(\frac{7}{3}+\frac{7}{2}\right)\times x=\frac{-25}{6}+\frac{22}{7}$$\left(\frac{14+21}{6}\right)\times x=-\frac{25}{6}+\frac{22}{7}$$\frac{35}{6}\times x=-\frac{25}{6}+\frac{22}{7}$$x=\left(-\frac{25}{6}+\frac{22}{7}\right)\div\frac{35}{6}$$x=\left(-\frac{25}{6}+\frac{22}{7}\right)\times\frac{6}{35}$$x=-\frac{25}{6}\times\frac{6}{35}+\frac{22}{7}\times\frac{6}{35}$$x=-\frac{5}{7}+\frac{132}{245}$$x=-\frac{43}{245}$

Lê Nguyên Hạo · Answer

a. I2x + 1I = 3/5=> TH1 :  2x + 1 = 3/52x = 3/5 - 12x = -2/5x   = -2/5 : 2x   = -1/5=> TH2  2x + 1 = -3/5=> 2x = -3/5 - 1 => 2x = -8/5=> x  = -8/5 : 2=> x  = -4/5b/ x+3/4 = -7/2=> x + 3/4 = -14/4=> x + 3 = -14=> x       = -14 - 3=> x      = -17c. (7/2 - 2x).4/3 = 22/3 7/2 - 2x            = 22/3 :4/37/2 - 2x             = 11/22x                     = 7/2 - 11/2 2x                     = -2x                       = -1d. (7/3 + 7/2). x = -25/6 + 22/735/6.x               = -43/42x                      = -43/42 : 35/6x                      = -43/245Câu trả lời: a. I2x + 1I = 3/5=> TH1 :  2x + 1 = 3/52x = 3/5 - 12x = -2/5x   = -2/5 : 2x   = -1/5=> TH2  2x + 1 = -3/5=> 2x = -3/5 - 1 => 2x = -8/5=> x  = -8/5 : 2=> x  = -4/5b/ x+3/4 = -7/2=> x + 3/4 = -14/4=> x + 3 = -14=> x       = -14 - 3=> x      = -17c. (7/2 - 2x).4/3 = 22/3 7/2 - 2x            = 22/3 :4/37/2 - 2x             = 11/22x                     = 7/2 - 11/2 2x                     = -2x                       = -1d. (7/3 + 7/2). x = -25/6 + 22/735/6.x               = -43/42x                      = -43/42 : 35/6x                      = -43/245

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