Question

решите плиз
е) 5-1/3x-1/2=1/4x
з) x/3+x/2=6

Answer 1

 е) условие можно прочитать по-разному:
$5 - \frac{1}{3x} - \frac{1}{2} = \frac{1}{4x} \\ \\ 4 \frac{1}{2} - \frac{1}{3x} - \frac{1}{4x} = 0 \\ \\ \frac{9}{2} - \frac{1}{3x} - \frac{1}{4x} = 0 |*12x \\ \\ x \neq 0 \\ \\ 9 * 6x - 1*4 - 1*3 = 0*12x \\ \\ 54x - 7 = 0 \\ \\ 54x = 7 \\ \\ x = \frac{7}{54}$

$5 - \frac{1}{3}x - \frac{1}{2} = \frac{1}{4}x \\ \\ 4 \frac{1}{2} - \frac{1}{3}x = \frac{1}{4}x \\ \\ - \frac{1}{3}x - \frac{1}{4}x = - 4 \frac{1}{2} \\ \\ - \frac{1*4 + 1*3}{12} x = - \frac{9}{2} | * (-1)\\ \\ \frac{7}{12} x = \frac{9}{2} \\ \\ x = \frac{9}{2} :\frac{7}{12} = \frac{9}{2} * \frac{12}{7} = \frac{9*6}{1*7} = \frac{54}{7} \\ \\ x = 7 \frac{5}{7}$


з)
$\frac{x}{3} + \frac{x}{2} = 6 |*6 \\ \\ 2x + 3x = 6*6 \\ \\ 5x = 36 \\ \\ x= 36 : 5 \\ \\ x =7,2$