Đáp án:
Giải thích các bước giải:
(3$\dfrac{1}{2} - 2x) : 3\dfrac{1}{3} = 7\dfrac{1}{7}$
($\dfrac{7}{2} - 2x) : \dfrac{7}{3} = \dfrac{15}{7}$
($\dfrac{7}{2} - 2x) = \dfrac{15}{7} × \dfrac{7}{3}$
$\dfrac{7}{2} - 2x = 5$
2x = $\dfrac{7}{2} - 5$
$2x$ $=$ $\dfrac{-3}{2}$
$x$ $=$ $\dfrac{-3}{4}$