Đáp án:
$x=\dfrac{-1}{8}$
Giải thích các bước giải:
$2\dfrac{1}{5}(3\dfrac{1}{4}+2x)=6\dfrac{3}{5}$
$→\dfrac{11}{5}(\dfrac{13}{4}+2x)=\dfrac{33}{5}$
$→\dfrac{13}{4}+2x=\dfrac{33}{5}:\dfrac{11}{5}$
$→\dfrac{13}{4}+2x=3$
$\to 2x=3-\dfrac{13}{4}$
$\to 2x=\dfrac{-1}{4}$
$\to x=\dfrac{-1}{4}:2$
$\to x=\dfrac{-1}{8}$
Vậy $x=\dfrac{-1}{8}$