Question

tìm x biết

a, \(\dfrac{5}{6}\) - x = \(\dfrac{3}{12}\)

b,\(\dfrac{12}{7}\) : x + \(\dfrac{9}{10}\)= \(\dfrac{7}{5}\)

Answer 1

Mọi người giúp mk với

Answer 2

a, $\frac{5}{6}$ - x = $\frac{3}{12}$

\(x=\dfrac{5}{6}-\dfrac{3}{12}\)

\(x=\dfrac{7}{12}\)

b,$\frac{12}{7}$ : x + $\frac{9}{10}$= $\frac{7}{5}$

\(\dfrac{12}{7}\div x=\dfrac{7}{5}-\dfrac{9}{10}\)

\(\dfrac{12}{7}\div x=\dfrac{5}{10}\)

\(x=\dfrac{12}{7}\div\dfrac{5}{10}\)

\(x=\dfrac{24}{7}\)

Answer 3

a) \(\dfrac{5}{6}-x=\dfrac{3}{12}\)

\(\dfrac{10}{12}-x=\dfrac{3}{12}\)

\(x=\dfrac{10}{12}-\dfrac{3}{12}\)

\(x=\dfrac{7}{12}\)

b) \(\dfrac{12}{7}:x+\dfrac{9}{10}=\dfrac{7}{5}\)

\(\dfrac{12}{7}:x=\dfrac{7}{5}-\dfrac{9}{10}\)

\(\dfrac{12}{7}:x=\dfrac{14}{10}-\dfrac{9}{10}\)

\(\dfrac{12}{7}:x=\dfrac{1}{2}\)

\(x=\dfrac{12}{7}:\dfrac{1}{2}\)

\(x=\dfrac{12}{7}\cdot2\)

\(x=\dfrac{24}{7}\)

Answer 4

a,\(\dfrac{5}{6}-x=\dfrac{3}{12}\)

\(x=\dfrac{5}{6}-\dfrac{3}{12}\)

\(x=\dfrac{10}{12}-\dfrac{3}{12}\)

\(x=\dfrac{7}{12}\)

Vậy \(x=\dfrac{7}{12}\)

b,\(\dfrac{12}{7}\div x+\dfrac{9}{10}=\dfrac{7}{5}\)

​\(\dfrac{12}{7}\div x+\dfrac{9}{10}=\dfrac{14}{10}\)​

\(\dfrac{12}{7}\div x\) \(=\dfrac{14}{10}-\dfrac{9}{10}\)

\(\dfrac{12}{7}\div x\) \(=\dfrac{1}{2}\)

\(x\) \(=\dfrac{12}{7}\div\dfrac{1}{2}\)

\(x\) \(=\dfrac{12}{7}.\dfrac{2}{1}\)

\(x\) \(=\dfrac{24}{7}\) Vậy \(x\) \(=\dfrac{24}{7}\)