Решить уровнение: а) 2 3-х = 16 б) 3 2 х + 7 = 9 3 х + 15 в) Log3 (5 х + 3) = Log3 (7 х + 5)

Найдем корни.

а) 2 / (3 - х) = 16;

Умножим накрест.

16 * (3 - x) = 2;

3 - x = 2/16;

3 - x = 1/8;

-x = 1/8 - 3;

-x = 1/8 - 8/8 - 2;

-x = - 2 - 7/8;

-x = - 2 7/8;

x = 2 7/8.

б) 3 / (2 * х + 7) = 9;

9 * (2 * x + 7) = 3;

2 * x + 7 = 3/9;

2 * x + 7 = 1/3;

2 * x = 1/3 - 7;

2 * x = - 6 2/3;

2 * x = - 20/3;

x = - 10/3.

в) Log3 (5 * х + 3) = Log3 (7 * х + 5);

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

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

-2 * x = 2;

x = - 2/2;

x = - 1.