Câu hỏi của Hoàng Thúy An

Question

tìm x

$-1.2+20\%x=\dfrac{1}{3}x-1\dfrac{1}{4}$

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Adonis Baldric · Accepted Answer

$-1,2+20\%x=\dfrac{1}{3}x-1\dfrac{1}{4}$

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

$\Rightarrow\dfrac{1}{3}x-\dfrac{1}{5}x=\dfrac{5}{4}+\left(-1,2\right)$

$\Rightarrow\dfrac{2}{15}x=\dfrac{1}{20}\Rightarrow x=\dfrac{1}{20}\div\dfrac{2}{15}=\dfrac{3}{8}$

Vậy x = $\dfrac{3}{8}$Câu trả lời: $-1,2+20\%x=\dfrac{1}{3}x-1\dfrac{1}{4}$

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

$\Rightarrow\dfrac{1}{3}x-\dfrac{1}{5}x=\dfrac{5}{4}+\left(-1,2\right)$

$\Rightarrow\dfrac{2}{15}x=\dfrac{1}{20}\Rightarrow x=\dfrac{1}{20}\div\dfrac{2}{15}=\dfrac{3}{8}$

Vậy x = $\dfrac{3}{8}$

Đại số lớp 7