Question

Сроооочноооооооооооооо
Решить систему уравнений ​

Answer 1

Ответ:2B
3A
4C

Объяснение:

Answer 2

2. Ответ: В)

$\left \{ {{ \frac{x}{3} + \frac{y}{2} = 1 } \atop {x + 3y = 0}} \right. \\ \\ \left \{ {{ \frac{2x + 3y}{6} = 1 \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: } \atop {x + 3y = 0 \: \:| \times ( - 1) }} \right. \\ \\ \left \{ {{2x + 3y = 6} \atop { - x - 3y = 0}} \right. + \\ x = 6$ \\ $x + 3y = 0 \\ 6 + 3y = 0 \\ 3y = - 6 \\ y = - 2$

3. Ответ: С)

$[tex]\left \{ {{ \frac{8x - 3y}{5} + 3x = 4} \atop { \frac{7y - 2x}{5} - 2y = - 1}} \right. \\ \\ \left \{ {{ \frac{8x - 3y + 15x}{5} = 4} \atop { \frac{7y - 2x - 10y}{5} }} \right. = - 1 \\ \\ \left \{ {{23x - 3y = 20 \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: } \atop { - 3y - 2x= - 5 \: \:| \times - (1)}} \right. \\ \\ \left \{ {{23x - 3y = 20} \atop {3y + 2x = 5}} \right. + \\ 25x = 25 \: \: \: \: x = 1$

И вместо х поставим 1

$3y + 2x = 5 \\ 3y + 2 \times 1 = 5 \\ 3y + 2 = 5 \\ 3y = 3 \\ y = 1$[/tex]

И вместо х поставим 1

$23x - 3y = 20 \\ 23 \times 1 - 3y = 20 \\ 23 - 3y = 20 \\ - 3y = - 3 \\ y = 1$

4. Ответ: D)

$[tex]\left \{ {{ \frac{x + y}{2} - \frac{x - y}{3} = 2 \frac{5}{6} } \atop { \frac{x + y}{3} + \frac{ {y - x} }{4} = 1 \frac{11}{12} }} \right. \\ \\ \left \{ {{ \frac{3x + 3y - 2x + 2y}{6} = \frac{17}{6} } \atop { \frac{4x + 4y + 3y - 3x}{12} = \frac{23}{12} }} \right. \\ \\ \left \{ {{18x + 18y - 12x + 12y = 102} \atop {48x + 48y + 36y - 36x = 276}} \right. \\ \\ \left \{ {{6x + 30y = 102 \: \:| \times ( - 2) } \atop {12x + 84y = 276 \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: }} \right.$

$\left \{ {{ - 12x - 60y = - 204} \atop {12x + 84y = 276}} \right. + \\ 24y = 72 \\ y = 3$

И вместо у поставим 3

$6x + 30y = 102 \\ 6x + 30 \times 3 = 102 \\ 6x + 90 = 102 \\ 6x = 12 \\ x = 2$