Câu hỏi của Yến Nhi Sky M-tp

Question

a. |x-1/2|=3/4

b. |4/3+x|=2/5

Võ Đông Anh Tuấn · Accepted Answer

a ) $\left|x-\dfrac{1}{2}\right|=\dfrac{3}{4}$

$\Leftrightarrow\left[{}\begin{matrix}x-\dfrac{1}{2}=\dfrac{3}{4}\x-\dfrac{1}{2}=-\dfrac{3}{4}\end{matrix}\right.$

$\Leftrightarrow\left[{}\begin{matrix}x=\dfrac{5}{4}\x=-\dfrac{1}{4}\end{matrix}\right.$

Vậy ...................

b ) $\left|\dfrac{4}{3}+x\right|=\dfrac{2}{5}$

$\Leftrightarrow\left[{}\begin{matrix}\dfrac{4}{3}+x=\dfrac{2}{5}\\dfrac{4}{3}+x=-\dfrac{2}{5}\end{matrix}\right.$

$\Leftrightarrow\left[{}\begin{matrix}x=-\dfrac{14}{15}\x=-\dfrac{26}{15}\end{matrix}\right.$

Vậy .......Câu trả lời: a ) $\left|x-\dfrac{1}{2}\right|=\dfrac{3}{4}$

$\Leftrightarrow\left[{}\begin{matrix}x-\dfrac{1}{2}=\dfrac{3}{4}\x-\dfrac{1}{2}=-\dfrac{3}{4}\end{matrix}\right.$

$\Leftrightarrow\left[{}\begin{matrix}x=\dfrac{5}{4}\x=-\dfrac{1}{4}\end{matrix}\right.$

Vậy ...................

b ) $\left|\dfrac{4}{3}+x\right|=\dfrac{2}{5}$

$\Leftrightarrow\left[{}\begin{matrix}\dfrac{4}{3}+x=\dfrac{2}{5}\\dfrac{4}{3}+x=-\dfrac{2}{5}\end{matrix}\right.$

$\Leftrightarrow\left[{}\begin{matrix}x=-\dfrac{14}{15}\x=-\dfrac{26}{15}\end{matrix}\right.$

Vậy .......

qwerty · Answer

a) $\left|x-\dfrac{1}{2}\right|=\dfrac{3}{4}$

$\Leftrightarrow\left[{}\begin{matrix}x-\dfrac{1}{2}=\dfrac{3}{4}\x-\dfrac{1}{2}=-\dfrac{3}{4}\end{matrix}\right.$

$\Leftrightarrow\left[{}\begin{matrix}x=\dfrac{3}{4}+\dfrac{1}{2}\x=-\dfrac{3}{4}+\left(-\dfrac{1}{2}\right)\end{matrix}\right.$

$\Leftrightarrow\left[{}\begin{matrix}x=\dfrac{5}{4}\x=-\dfrac{1}{4}\end{matrix}\right.$

Vậy $x=\dfrac{5}{4}$ hoặc $x=-\dfrac{1}{4}$

b) $\left|\dfrac{4}{3}+x\right|=\dfrac{2}{5}$

$\Leftrightarrow\left[{}\begin{matrix}\dfrac{4}{3}+x=\dfrac{2}{5}\\dfrac{4}{3}+x=-\dfrac{2}{5}\end{matrix}\right.$

$\Leftrightarrow\left[{}\begin{matrix}x=\dfrac{2}{5}-\dfrac{4}{3}\x=-\dfrac{2}{5}-\dfrac{4}{3}\end{matrix}\right.$

$\Leftrightarrow\left[{}\begin{matrix}x=-\dfrac{14}{15}\x=-\dfrac{26}{15}\end{matrix}\right.$

Vậy $x=-\dfrac{14}{15}$ hoặc $x=-\dfrac{26}{15}$Câu trả lời: a) $\left|x-\dfrac{1}{2}\right|=\dfrac{3}{4}$

$\Leftrightarrow\left[{}\begin{matrix}x-\dfrac{1}{2}=\dfrac{3}{4}\x-\dfrac{1}{2}=-\dfrac{3}{4}\end{matrix}\right.$

$\Leftrightarrow\left[{}\begin{matrix}x=\dfrac{3}{4}+\dfrac{1}{2}\x=-\dfrac{3}{4}+\left(-\dfrac{1}{2}\right)\end{matrix}\right.$

$\Leftrightarrow\left[{}\begin{matrix}x=\dfrac{5}{4}\x=-\dfrac{1}{4}\end{matrix}\right.$

Vậy $x=\dfrac{5}{4}$ hoặc $x=-\dfrac{1}{4}$

b) $\left|\dfrac{4}{3}+x\right|=\dfrac{2}{5}$

$\Leftrightarrow\left[{}\begin{matrix}\dfrac{4}{3}+x=\dfrac{2}{5}\\dfrac{4}{3}+x=-\dfrac{2}{5}\end{matrix}\right.$

$\Leftrightarrow\left[{}\begin{matrix}x=\dfrac{2}{5}-\dfrac{4}{3}\x=-\dfrac{2}{5}-\dfrac{4}{3}\end{matrix}\right.$

$\Leftrightarrow\left[{}\begin{matrix}x=-\dfrac{14}{15}\x=-\dfrac{26}{15}\end{matrix}\right.$

Vậy $x=-\dfrac{14}{15}$ hoặc $x=-\dfrac{26}{15}$

Mashiro Shiina · Answer

$\left|x-\dfrac{1}{2}\right|=\dfrac{3}{4}$

$\Leftrightarrow x-\dfrac{1}{2}=\dfrac{3}{4}\Rightarrow x=\dfrac{5}{4}$

$\Leftrightarrow x-\dfrac{1}{2}=-\dfrac{3}{4}\Rightarrow x=\dfrac{-1}{4}$
$\left|\dfrac{4}{3}+x\right|=\dfrac{2}{5}$

$\dfrac{4}{3}+x=\dfrac{2}{5}\Rightarrow x=\dfrac{-14}{15}$

$\dfrac{4}{3}+x=-\dfrac{2}{5}\Rightarrow x=-\dfrac{26}{15}$Câu trả lời: $\left|x-\dfrac{1}{2}\right|=\dfrac{3}{4}$

$\Leftrightarrow x-\dfrac{1}{2}=\dfrac{3}{4}\Rightarrow x=\dfrac{5}{4}$

$\Leftrightarrow x-\dfrac{1}{2}=-\dfrac{3}{4}\Rightarrow x=\dfrac{-1}{4}$
$\left|\dfrac{4}{3}+x\right|=\dfrac{2}{5}$

$\dfrac{4}{3}+x=\dfrac{2}{5}\Rightarrow x=\dfrac{-14}{15}$

$\dfrac{4}{3}+x=-\dfrac{2}{5}\Rightarrow x=-\dfrac{26}{15}$

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