Решите уравнение:
а) 0,71x − 13 = 9 − 0,39x;
б) $1,2 + \frac{3}{10}x = \frac{8}{15}x + 0,78$;
в) 8x − 1,79 = 4,61 − 8x;
г) $\frac{5}{12}x + 1,3 = 0,53 + \frac{7}{8}x$.
0,71x − 13 = 9 − 0,39x
0,71x + 0,39x = 9 + 13
x = 20
$1,2 + \frac{3}{10}x = \frac{8}{15}x + 0,78$
$\frac{3}{10}x - \frac{8}{15}x = 0,78 - 1,2$
$\frac{9}{30}x - \frac{16}{30}x = -0,42$
$-\frac{7}{30}x = -\frac{42}{100}$
$x = \frac{21}{50} : \frac{7}{30}$
$x = \frac{21}{50} * \frac{30}{7}$
$x = \frac{3}{5} * \frac{3}{1}$
$x = \frac{9}{5} = 1\frac{4}{5}$
8x − 1,79 = 4,61 − 8x
8x + 8x = 4,61 + 1,79
16x = 6,4
x = 0,4
$\frac{5}{12}x + 1,3 = 0,53 + \frac{7}{8}x$
$\frac{5}{12}x - \frac{7}{8}x = 0,53 - 1,3$
$\frac{10}{24}x - \frac{21}{24}x = -0,77$
$-\frac{11}{24}x = -\frac{77}{100}$
$x = \frac{77}{100} : \frac{11}{24}$
$x = \frac{77}{100} * \frac{24}{11}$
$x = \frac{7}{25} * \frac{6}{1}$
$x = \frac{42}{25} = 1\frac{17}{25}$
Пожауйста, оцените решение
