Решите уравнения: 3 (х+5) = 7-5 х 19 (у-9) = 3 (у+7) 4 (х-9) = 3 (х-8) 3 (2 х-9) = 5 (х-4) 7 (3-2 х) = 15 (1-х)

Найдем корни.

1) 3 * (х + 5) = 7 - 5 * х;

3 * x + 15 = 7 - 5 * x;

3 * x + 5 * x = 7 - 15;

8 * x = - 8;

x = - 8/8;

x = - 1.

2) 19 * (у - 9) = 3 * (у + 7);

19 * (y - 9) - 3 * (y + 7) = 0;

19 * y - 3 * y - 171 - 21 = 0;

16 * y - 192 = 0;

y = 192/16;

y = 12.

3) 4 * (х - 9) = 3 * (х - 8);

4 * x - 3 * x = - 24 + 36;

x = 12.

5) 3 * (2 * х - 9) = 5 * (х - 4);

6 * x - 5 * x = - 20 + 27;

x = 7.

6) 7 * (3 - 2 * х) = 15 * (1 - х);

-14 * x + 15 * x = 15 - 21;

x = - 7.