Question

Решить примеры, а то как-то запутался в дробях : '(

Answer 1

$\frac{5}{6} ( \frac{1}{2} x - \frac{2}{3} ) = 3x - 2 \frac{1}{4} \\ \\ \frac{5}{12} x - \frac{10}{18} = 3x - 2 \frac{1}{4} \\ \\ \frac{5}{12} x - \frac{5}{9} = 3x - 2 \frac{1}{4} \\ \\ \frac{5}{12} x - 3x = - 2 \frac{1}{4}+ \frac{5}{9} \\ \\ - 2 \frac{7}{12} x = \frac{-81+20}{36} \\ \\ - \frac{31}{12} x = - \frac{61}{36} \\ \\ x= - \frac{61}{36} : (- \frac{31}{12}) = \frac{61}{36} * \frac{12}{31} = \frac{61*1}{3*31} \\ \\ x= \frac{61}{93}$

проверим:
$\frac{5}{6} ( \frac{1}{2} * \frac{61}{93} - \frac{2}{3} ) = 3* \frac{61}{93} - 2 \frac{1}{4} \\ \\ \frac{5}{6} ( \frac{61}{186} - \frac{124}{186} ) = \frac{183}{93} - \frac{9}{4} \\ \\ \frac{5}{6} * (- \frac{63}{186} ) = \frac{732-837}{372} \\ \\ - \frac{5*7}{2*62} = \frac{732-837}{372} \\ \\ - \frac{35}{124} = - \frac{105:3}{372:3} \\ \\ - \frac{35}{124} =- \frac{35}{124}$

$- 4 \frac{5}{6} +3 \frac{3}{23} (-11 \frac{4}{9} - (-3,6) : \frac{9}{35} ) = \\ \\ =- 4 \frac{5}{6} +3 \frac{3}{23} (-11 \frac{4}{9} - (- \frac{36*35}{10*9} ) = \\ \\ =- 4 \frac{5}{6} +3 \frac{3}{23} (-11 \frac{4}{9} -(- \frac{2*7}{1*1} )) = \\ \\ =- 4 \frac{5}{6} +\frac{3*23+3}{23} (-11 \frac{4}{9} +14 ) = \\ \\ =- 4 \frac{5}{6} + \frac{72}{23} * \frac{23}{9} = - 4 \frac{5}{6} +8 = 3 \frac{1}{6}$

проверим по действиям:
$1) (-3,6) : \frac{9}{35}=- \frac{36}{10} * \frac{35}{9} = - \frac{4*7}{2*1} = - (2*7) =-14 \\ \\ 2) -11 \frac{4}{9} -(-14) = 2 \frac{5}{9} \\ \\ 3) 3 \frac{3}{23}* 2 \frac{5}{9} = \frac{72*23}{23*9} = 8 \\ \\ 4) -4 \frac{5}{6} +8 = 3 \frac{1}{6}$

Answer 2

Я решила как смогла!