15+2 (x+3y) = 3 (4x+y) 2 (5x-y) - 3y=2+3 (2x-y) 2) 5 (7x+2y) - 11y=6 (2x+y) + 2 33+3 (6x-5y) = 3 (x+2y) - 5y

Вычислим решение системы:

1) { 15 + 2 * (x + 3 * y) = 3 * (4 * x + y);

2 * (5 * x - y) - 3 * y = 2 + 3 * (2 * x - y);

Упростим равенства.

{ 15 + 2 * x + 6 * y = 12 * x + 3 * y;

10 * x - 2 * y - 3 * y = 2 + 6 * x - 3 * y;

{ 15 - 10 * x + 3 * y = 0;

2 - 4 * x - y = 0;

{ 15 - 10 * x + 3 * y = 0;

6 - 12 * x - 3 * y = 0;

Сложим равенства.

15 + 6 - 10 * x - 12 * x = 0;

21 - 22 * x = 0;

x = 21/22.

Найдем у.

2 - 4 * x = у;

y = 2 - 4 * 21/22 = 2 - 2 * 21/11 = 2 - 42/11 = 22/11 - 42/11 = - 20/11.

Ответ: (21/22; - 20/11).

2) { 5 * (7 * x + 2 * y) - 11 * y = 6 * (2 * x + y) + 2;

33 + 3 * (6 * x - 5 * y) = 3 * (x + 2 * y) - 5 * y;

{ 35 * x + 10 * y - 11 * y = 12 * x + 6 * y + 2;

35 + 18 * x - 15 * y = 3 * x + 6 * y - 5 * y;

{ 35 * x - y = 12 * x + 6 * y + 2;

35 + 18 * x - 15 * y = 3 * x + y;

{ 23 * x - 7 * y - 2 = 0;

35 + 15 * x - 16 * y = 0;

{ y = (23 * x - 2) / 7;

1. 35 + 15 * x - 16 * (23 * x - 2) / 7 = 0;

245 + 105 * x - 23 * x + 2 = 0;

82 * x = - 27;

x = - 247/82;

2. y = (23 * x - 2) / 7;

y = (23 * (-247/82) - 2) / 7 = (-5681/81 - 2) / 7 = - 5843/81 * 1/7 = - 5843/567;

Ответ: (-247/82; - 5843/567).