Реши уравнение:7*(х+6)=49;15*(х-10)=255;27*(19-х)=324;3*(2х-9)=27;9*(5х+8)=207;19*(39-2х)=703;2*(2х+3х)=20;7*(3х-х)=42;12*(х+9х)=1200

Вычислим корешки:

1) 7 * (х + 6) = 49;

x + 6 = 49/7;

x + 6 = 7;

x = 7 - 6;

x = 1.

2) 15 * (х - 10) = 255;

x - 10 = 255/15;

x - 10 = 17; 

x = 17  + 10;

x = 27.

3) 27 * (19 - х) = 324;

19 - x = 324/27;

19 - x = 12; 

x = 19 - 12;

x = 7.

4) 3 * (2 * х - 9) = 27;

2 * x - 9 = 9;

x =18/2;

x = 9.

5) 9 * (5 * х + 8) = 207;

5 * x + 8 = 23; 

5 * x = 15;

x = 3.

6) 19 * (39 - 2 * х) = 703;

39 - 2 * x = 37; 

2 * x = 2;

x = 1.

7) 2 * (2 * х + 3 * х) = 20;

5  * x = 10;

x = 2.

8) 7 * (3 * х - х) = 42;

2 * x = 6;

x = 3.

9) 12 * (х + 9 * х) = 1 200; 

12 * 10 * x = 1200; 

x = 1 200/120; 

x = 10.