решите уравнение 1.84a+25a+7=443 2.4(9+7x)+2 3.486(5x+2)=18 4.5(14+b)+6b=158

Решим уравнения:

1) 84 * a + 25 * a + 7 = 443; 

a * (84 + 25) + 7 = 443;

a * 109 + 7 = 443;

109 * a + 7 = 443;

109 * a = 443 - 7;

109 * a = 436;

a = 436/109;

a = 4;

Ответ: а = 4.

2) 4 * (9 + 7 * x) = 2; 

9 + 7 * x = 2/4;

9 + 7 * x = 0.5;

7 * x = 0.5 - 9;

7 * x = -8.5;

x = -8.5/7;

x = -85/70;

Ответ: х = -85/70.

3) 486/(5 * x + 2) = 18; 

18 * (5 * x + 2) = 486;

5 * x + 2 = 486/18;

5 * x + 2 = 27;

5 * x = 27 - 2;

5 * x = 25;

x = 25/5;

x = 5;

Ответ: х = 5.

4) 5 * (14 + b) + 6 * b = 158; 

5 * 14 + 5 * b + 6 * b = 158; 

70 + 5 * b + 6 * b = 158; 

11 * b + 70 = 158; 

11 * b = 158 - 70; 

11 * b = 88; 

b = 88/11; 

b = 8.