a)$\frac{2}{3}$.x+$\frac{1}{5}$=$\frac{7}{10}$-x
b)3$\frac{2}{9}$:1$\frac{1}{9}$-$\frac{46}{5}$.$\frac{5}{23}$+$\frac{4}{5}$
c)(3$\frac{4}{5}$-2.x).1$\frac{1}{3}$=5$\frac{5}{7}$
a)$\frac{2}{3}$.x+$\frac{1}{5}$=$\frac{7}{10}$-x
b)3$\frac{2}{9}$:1$\frac{1}{9}$-$\frac{46}{5}$.$\frac{5}{23}$+$\frac{4}{5}$
c)(3$\frac{4}{5}$-2.x).1$\frac{1}{3}$=5$\frac{5}{7}$
Đáp án:
$a/$ `2/3x + 1/5 = 7/10 – x`
`-> 2/3x + 1/5 – 7/10 + x = 0`
`-> (2/3x + x) + (1/5 – 7/10) = 0`
`-> 5/3x – 1/2 = 0`
`-> 5/3x = 1/2`
`-> x = 3/10`
`text{Vậy}` `x = 3/10`
$b/$ `3 2/9 : 1 1/9 – 46/5 . 5/23 + 4/5`
`= 29/9 . 9 – 2 + 4/5`
`= 29 – 2 + 4/5`
`= 27 + 4/5`
`= 139/5`
$c/$ `(3 4/5 – 2x) . 1 1/3 = 5 5/7`
`-> (19/5 – 2x) . 4/3 = 40/7`
`-> 19/5 – 2x = 30/7`
`-> 2x = (-17)/35`
`-> x = (-17)/70`
`text{Vậy}` `x = (-17)/70`