Question

решите уравнение пожалуйста! с решением и ответом.
(срочно)
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Answer 1

( 3 )

$(\frac{7}{8}-0,2)*x=8,1\\\\(\frac{7}{8}-\frac{2}{10})*x=\frac{81}{10}\\\\(\frac{35}{40}-\frac{8}{40})*x=\frac{81}{10} \\\\\frac{27}{40}*x=\frac{81}{10}\\\\x=\frac{81}{10}:\frac{27}{40}\\\\x=\frac{81}{10}*\frac{40}{27}\\\\x=\frac{3}{1} *\frac{4}{1}\\\\x=12$

Проверка:

$(\frac{7}{8}-0,2)*12=8,1\\\\(\frac{7}{8}-\frac{2}{10} )*12=\frac{81}{10}\\\\(\frac{35}{40}-\frac{8}{40} )*12=\frac{81}{10} \\\\\frac{27}{40} *12=\frac{81}{10}\\\\\frac{324}{40}=\frac{81}{10}\\\\\frac{81}{10}=\frac{81}{10}\\\\8,1=8,1$

( 4 )

$(4-2\frac{3}{7})*x=2\frac{5}{14} \\\\(\frac{4}{1} -\frac{17}{7})*x=\frac{33}{14} \\\\(\frac{28}{7} -\frac{17}{7})*x=\frac{33}{14}\\\\\frac{11}{7}*x=\frac{33}{14}\\\\x=\frac{33}{14}:\frac{11}{7}\\\\x=\frac{33}{14}*\frac{7}{11}\\\\x=\frac{3}{2}*\frac{1}{1}\\\\x=\frac{3}{2}\\\\x=1,5$

Проверка:

$(4-2\frac{3}{7})*1,5=2\frac{5}{14} \\\\(\frac{4}{1} -\frac{17}{7})*\frac{3}{2} =\frac{33}{14} \\\\(\frac{28}{7} -\frac{17}{7})*\frac{3}{2} =\frac{33}{14}\\\\\frac{11}{7}*\frac{3}{2} =\frac{33}{14}\\\\\frac{33}{14}=\frac{33}{14}\\\\2\frac{5}{14}=2\frac{5}{14}$