Đáp án:
c) $x_{}$ = $\dfrac{9}{73}$
d) $x=-1_{}$
Giải thích các bước giải:
c) $4\frac{2}{3}$ - $(\frac{3}{5}:x)=-20$%
$\frac{14}{3}$ - $(\frac{3}{5}$: $x)$ = $-0,2$
$-(\frac{3}{5}:x)$ = $-0,2_{}$ $-\frac{14}{3}$
$\frac{3}{5}:x$ = $0,2+\frac{14}{3}_{}$
$\frac{3}{5}:x$ = $\frac{73}{15}$
$x_{}$ = $\frac{3}{5}:\frac{73}{15}$
$x_{}$ = $\dfrac{9}{73}$
d) $70_{}$%$x$ = $1\frac{1}{2}$ + $2,2x_{}$
$0,7x=\frac{3}{2}+2,2x_{}$
$0,7x-2,2x=\frac{3}{2}_{}$
$-\frac{3}{2}x=\frac{3}{2}_{}$
$x_{}$ = $\frac{3}{2}$ : $(-\frac{3}{2})$
$x=-1_{}$
