x-3/4=1 x+-3/7=4/7 3/2.x=-2/3 2/5+3/5.x=-1/4

Đáp án:

a)

x-$\frac{3}{4}$ =1

=>x = 1 + $\frac{3}{4}$

=>x = $\frac{7}{2}$

Vậy x ={$\frac{7}{2}$}

b)

x +$\frac{-3}{7}$ = $\frac{4}{7}$ 

=>x = $\frac{4}{7}$  + $\frac{3}{7}$

=>x =1

Vậy x={1}

c)

$\frac{3}{2}$.x = $\frac{-2}{3}$

=>x = $\frac{-2}{3}$ : $\frac{3}{2}$

=> x  = $\frac{-4}{9}$

Vậy x ={ $\frac{-4}{9}$}

d)

$\frac{2}{5}$ + $\frac{3}{5}$ .x = $\frac{-1}{4}$

=> $\frac{3}{5}$x= $\frac{-1}{4}$ -$\frac{2}{5}$

=>$\frac{3}{5}$x = $\frac{-13}{20}$ 

=> x = $\frac{-13}{20}$  : $\frac{3}{5}$

=>x = $\frac{-13}{12}$

Vậy x = { $\frac{-13}{12}$}

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