Решите уравнения 11 + 3х=55 + 4х. -15-4х=-8х+ 45. -8х-17=3х-105. 2(у+3)=21-3у

Найдем корешки. 

1) 11 + 3 * х = 55 + 4  * х; 

3 * x - 4 * x = 55 - 11;

x * (3 - 4) = 44;

x * (-1) = 44;

-x = 44;

x = -44.

2) -15 - 4 * х = -8 * х +  45; 

-4 * x + 8 * x = 45 - 15;

8 * x - 4 * x = 30;

4 * x = 30;

2 * x = 15;

x = 15/2;

x = 7.5.

3) -8 * х - 17 = 3 * х - 105; 

-8 * x - 3 * x = -105 + 17;

-11 * x = -88;

x = 88/11;

x = 8.

4) 2 * (у + 3) = 21 - 3 * у; 

2 * y + 6 = 21 - 3 * y; 

2 * y + 3 * y = 21 - 6; 

5 * y = 15; 

y = 15/5; 

y = 3.